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Unable to load dll HRESULT: 0x8007007E

I have moved a C# project from Visual Studio 2003 to Visual Studio 2005 Express.

I get the "unable to load dll HRESULT 0x8007007E" error when making a call to an unmanaged dll. This previously worked OK before.

I have tried putting the dll into the bin\debug directory, the windows and system32 directories with no success.

I have also added the debug directory to the environment path variable but still no success.

I have investigated trying to put a dependancy in the project on the dll but can't find a method of achieving this.

I have also tried running the application and the dll outside of the IDE in the same directory and it still can't find the dll.

Is there a difference in the way Framework 2.0 loads unmanged dlls compared to 1.1?

Additional information. I have both 1.1 and 2.0 Frameworks installed. The project still works in Visual Studio 2003.

Any help would be appreciated.




7 Answers Found


Answer 1

The DLL might itself require some other DLL.  In case of doubt, use Dependency Walker...


Answer 2


Its not until somebody says something blindingly obvious that a light bulb switches on.



Answer 3

I had the same issue before. You have to check two choices...

1- You location isn't correct
2 - You have dependencies. Maybe in your Visual Studio 2003 you had another path within your project  path. Check them to see what it is. Some folder is included you need to find which.

Take a look at http://www.dependencywalker.com/ and you can see if your dll  requires another dll.

Answer 4


I'm looking for a solution for a same kind of problem.

I have a visual  studio 2005 vb-service which make use of multiple dlls.

These dlls exist in two versions: say unicode and not unicode.

The difference in a pair of dlls is made by build configurations in visual studio  6.

Some of this dlls have dependencies on other ones.

However, my unicode dll  still has dependencies with some non-unicode ones where it depends on.

And this generates an error in my service ( Unable to load  dll ... )

I have checked all the settings in my project  and even make some changes in the dsp-file but still it gives the same error.

Can someone give my an advice that brings me closer to a breakthrough?

Thanks in advance.


Answer 6

I'm problem with my WINDOWS XP PROFESSIONAL SP2- in OPEN the Windows, see a message:

your SQLServer Installation is either corrupt or has been tampered with (Unable to Load SQLBOOT.DLL)  HRESULT 0x8007007e  please uninstall then re-run setup to correct this problem.






Answer 7

Hi All,

Could you Please confirm ---You have the SQL server in it but it is faling to start the SQL serverand Logging the error Unable to Load SQLBOOT.DLL


Try to copy the SQLBOOT.DLL from your SQL serverInstallation kit and Paste to the

following location "C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\Binn     "


Seems the SQLBOOT.DLL is missed or corrupted do the aboce steps as I mentioned and try to start it.


Thanks and Regards,



coming up withn this message when am abt to uninstall sql server 2008
I get Exception from HRESULT 0x8007007E when I try to backup with syncToy
while building a program, then press VS2010 Unable to load DLL 'FileTracker.dll' when I look back on all my machines Forum implementation missing file C: \ Windows \ Microsoft.NET \ Framework \ v4.0.21006 \ File Tracker. dll, which can lead v4 0. V4 30 128 and .0.30319. Should not my chapter vtrinh construction. expect people to help

Hi friends,


I am trying to convert pdf file to imagefiles for that i am using dll solidframe work but i am getting the exception  "Unable to load DLL 'Framework.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)".


How to add framework dll


thanks in advance.



I have created a web site and using System.Data.SqlServerCE dll. 

I added this dll from the path:"C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\System.Data.SqlServerCe.dll" 

And I run the web site in MS visual studio 2005 and all work fine and no error.

I created a virtual directory and deployed my web site to the server. Then tried to browse the page.

But when i tried to Browse the page on the Virtual Directory from server i got this error :.

Unable to load DLL 'sqlceme30.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)

I though i have missed out some dlls on server , so i tried to run my web site on the same server using Visual Studio 2005 but it still works perfectly. I dont know why when i deployed to the virtual directory then it become not working....

Can somebody advise me on this....i need it urgently...thanks x N


After Installation of VS2010 Beta 2, opening a VS208 project and try to build or rebuild it the following error messages (see below) is displayed. I do not use such a dll ! New projects in VS2010 were build correct.
Is my installation wrong ?
What is this dll for ?
What I have to do to build my existing VS2008 projekct ?
Thanks, Martin 

Error 1 The "GenerateResource" task failed unexpectedly.
System.DllNotFoundException: Unable to load DLL 'FileTracker.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
   at Microsoft.Build.Shared.NativeMethodsShared.InprocTracking.StartTrackingContextWithRoot(String intermediateDirectory, String taskName, String rootMarker)
   at Microsoft.Build.Utilities.FileTracker.StartTrackingContextWithRoot(String intermediateDirectory, String taskName, String rootMarkerResponseFile)
   at Microsoft.Build.Tasks.GenerateResource.Execute()
   at Microsoft.Build.BackEnd.TaskExecutionHost.Microsoft.Build.BackEnd.ITaskExecutionHost.Execute()
   at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask(ITaskExecutionHost taskExecutionHost, TaskLoggingContext taskLoggingContext, TaskHost taskHost, ItemBucket bucket, TaskExecutionMode howToExecuteTask, Boolean& taskResult) TestTheConnectors


I have a silverlight application, which is calling a WCF service.. this service uses SqlServer Spatial dll to perform some operations on my spatial data (since this dll cannot be used directly from the Silverlight app).

Here is the error:

 Unable to load DLL 'SqlServerSpatial.dll': Exception from HRESULT: 0xE06D7363

StackTrace:    at Microsoft.SqlServer.Types.GLNativeMethods.GeodeticIsValid(GeoMarshalData g, Boolean& result)
   at Microsoft.SqlServer.Types.GLNativeMethods.GeodeticIsValid(GeoData g)
   at Microsoft.SqlServer.Types.SqlGeography.IsValidExpensive()
   at Microsoft.SqlServer.Types.SqlGeography.ConstructGeographyFromUserInput(GeoData g, Int32 srid)
   at Microsoft.SqlServer.Types.SqlGeography.GeographyFromText(OpenGisType type, SqlChars taggedText, Int32 srid)
   at Microsoft.SqlServer.Types.SqlGeography.STGeomFromText(SqlChars geometryTaggedText, Int32 srid)
   at TerritoryMap.WebServices.SilverlightService.SaveSplit_County(String CountyToSplit_StateCode, String CountyToSplit_CountyCode, String SplitPolygonString) 

This error occurs when I get to this line in my service code:

SqlGeography splitPolygon = new SqlGeography();

            //Attempt to fill splitPolygon with data
                System.Data.SqlTypes.SqlString sString = new System.Data.SqlTypes.SqlString(SplitPolygonString);
                System.Data.SqlTypes.SqlChars sChars = new System.Data.SqlTypes.SqlChars(sString);

                splitPolygon = SqlGeography.STGeomFromText(sChars, 4326);                
            catch (Exception error)


the silverlight service passes this info for the parameter SplitPolygonString

POLYGON((-86.2613418066406 32.3300654708459,-86.6431167089844 32.7722523910741,-87.1210219824219 32.7144985351196,-86.9727065527344 32.1697880375832,-86.2778212988281 32.1907098274065,-86.2613418066406 32.3300654708459))

This code works great on my development machine (Win 7, Sql Express 2008 x64 SP2).. but not on my development server (Windows Server 2003 std, x32, Sql Std 2008 SP2 x32)

I've installed the VC++ redistributable, 2005, 2008 and 2010 as many sites have suggested on the server. I've also ran the SQLSysClrTypes.msi.  Any ideas on what I can check?


I am very new in programming.  I developed an application using SQL Server local database of the visual studio 2008.

the application runs correctly without any error on my 32 bit windows 7 system but when i installed it my friends 32 and 64 bit systems it threw an exception described below:


System.DllNotFoundException: Unable to load DLL 'sqlceme35.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
   at System.Data.SqlServerCe.NativeMethods.CreateErrorInstance(IntPtr& pError)
   at System.Data.SqlServerCe.SqlCeCommand..ctor()
   at ConferenceGENIUS.Database1DataSet4pix1TableAdapters.ReligiousDataTableAdapter.InitAdapter()
   at ConferenceGENIUS.Database1DataSet4pix1TableAdapters.ReligiousDataTableAdapter.get_Adapter()
   at ConferenceGENIUS.Database1DataSet4pix1TableAdapters.ReligiousDataTableAdapter.Fill(ReligiousDataDataTable dataTable)
   at ConferenceGENIUS.frmViewer.frmViewer_Load(Object sender, EventArgs e) 


Please i have read the past suggestions on similar issues but changing the target PC to x86 did not help solve the problem.

Please i need help urgently


I developed a simple desktop application on my 32 bit window7 systm using VS 2008. I used the local database on VS 2008. The app runs correctly on my system but when i installed it on my friends 32 bit syst the following runtime exception was thrown;

System.DllNotFoundException: Unable to load DLL 'sqlceme35.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)

I have read the blogs from ErikEJand others but it didnt help yet. please what can i do. I am new to programming

Please am waiting earnestly for your help



I am developing an application in C#.net compact environment for Window CE device.


When I try to call WCE DLL (it is written in EVC 4.0) in C#.net compact environment, I am not able to load it and getting error message

Unable to load DLL 'mydll.dll': Invalid access to memory location. (Exception from HRESULT: 0x800703E6)

 Can you please suggest me how to call WCE DLL in C#.net compact Framwork?


Hi Everyone,

This problem is driving me batty!

First of all my application is structured as follows:

1. An ASP.NET WEB application for user interface control and database reporting (SQL Express 2005 SP1)  I have a specially created user account that is used for impersonation.  Mainly to start & stop the windows service and also to pass startup arguments to the service.

2. A Windows service application that connects to a remote Postgre database on a UNIX system and gathers database records as they are created there.  I have to use a third-party (non .NET) DLL to do some manipulation of the records before storing them locally on the SQL database.

This all worked brilliantly on XP SP2 as well as Server 2003 R2.

On VISTA and Server 2008 (x86) however when I start the windows service (which loads the external DLL) I get this error:

"Unable to load DLL 'MPIest.dll': Invalid access to memory location. (Exception from HRESULT: 0x800703E6)"

I have tried numerous things including the addition of a Manifest into the service application that has the following settings:




<requestedExecutionLevellevel="requireAdministrator"uiAccess="false" />




Pleeeeease can someone tell me where I am going wrong or how to go about solving this problem... I have been going round in circles for days and my head's spinning...

Many thanks

I have .Net 1.1  Application that works fine with the same dll, after redesigning application to 2.o Framework I have this error, I tried to compile it with /MT (this is C++ project in ANSI C, planned to be working on different platforms), but had no luck. Even tryed to make dummy dll  with function doing nothing - still didn't work. What can be problem and how to fix it?
I have downloaded and installed visual studio C++ Express. And it works! So I searched for a way to deploy my application. Well, the MS Solution: Upgrade to visual studio 2008 standard.

So I bought visual studio 2008 standard upgrade and tried to install it. But I always get the error: Unable to load sitsetup.dll.

I am running Windows XP Home Edition 2002 Service Pack 3. On an Intel Mac under Parrallels 4.03844. Are there any copy-protections, which do not work under MAC emulation?

I have done all the updates and even installed Windows Installer 4.5 Redistributable hotfix. I did run fsc.exe
 /scannow. No file replacements were done.

What can I do? I think this should be a simple standard installation/Upgrade, especially since the C++ Express installation is working. Is there a possibility to Unpack the the cabinets separatly?

Any help appriciated. Thanks Felix.

When I select Analyze -> Profiler -> Attach/Detach, I get the error "Unable to load file or assembly VSPerfControl.interop.dll version =, system cannot find the file specified."

I found the file in C:\Program Files\Microsoft Visual Studio 10.0\Team Tools\Performance Tools. I registered it in the GAC and restarted VS 2010 and now I no longer receive the error. However putting it in the GAC seems like overkill. Can you tell me where VS2010 expects to be able to find this?

Thank you!

Jason Wells


Hello everyone

I am getting a weird problem.

The sharepoint site is working fine my old custom dlls (which i have created 2 days back).

I have just added some custom code and deployed the new dlls Now i see that site is not opening up.

I have cleared cache , done IISRESET but nothing has helped me.

The site is getting timeout after some time and the ULS logs are growing up like anything.

The new dlls does not have any code which will stop the site in loading up.

Any pointers are highly appreciated.






I am currently facing an issue where a mixed mode dll is unable to load in .net 4.0 when invoked dynamically. I am getting the following exception:

Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information.

I got to know that adding a config file with the follwoign info in the app would help:
  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0"/>

Now, the issue is, this dll can be used by many apps in Dev10. I need some mechanism to add config file with the dll, so that it works whenever the dll get loaded.
Is there a way to have dll.config file?


Similar to http://social.msdn.microsoft.com/Forums/en-US/rx/thread/362c4f49-05cd-4e72-bf9d-1042a63f2b0a, I'm trying to unit test a Silverlight 4 with RX 2617 project, this time with MSTest. 

I can run the unit tests fine, but when I try to debug them, constructing a subject (and therefore a scheduler) gives the following error:

Test method Tests.UnitTest1.TestMethod1 threw exception: 
System.TypeInitializationException: The type initializer for 'System.Concurrency.Scheduler' threw an exception. ---> System.DllNotFoundException: Unable to load DLL 'agcore': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
MS.Internal.XcpImports.Deployment_GetCurrentNative(IntPtr context, IntPtr& obj)
MS.Internal.XcpImports.Deployment_GetCurrent(IntPtr& pDeployment)
Tests.UnitTest1.TestMethod1() in c:\users\rfe\documents\visual studio 2010\Projects\RxUnitTestRepro\Tests\UnitTest1.cs: line 20

I think this would work if the static constructor for Scheduler could try to find out if Silverlight is actually running, and provide a test scheduler in that case.

I've put together a repro, please ask me if you'd like it emailed to you

Regards - Rob






Retrieving the COM class factory for component with CLSID {E1B87327-4DB5-492E-8AC2-F542BCA3C912} failed due to the following error: 80040154.

I have a .net dll refering Reg-Free COM DLL, when try to load my .net dll in AppDomain i get above error. If i regster it works fine. Also it works fine if i refer my .net dll from stand alond exe(works fine in both COM register and un-register scenarios). AppDomain is not recongnising Reg-Free COM dll.


I have to move a perfectly working web site from a perfectly working server to another host (heh, don't ask...).

We're using ABCpdf to generate PDF from web pages and so far, we never had problems until we tried moving to the new host. Here's the error:


Message: Exception of type 'System.Web.HttpUnhandledException' was thrown.
StackTrace: at System.Web.UI.Page.HandleError(Exception e)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
at System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
at System.Web.UI.Page.ProcessRequest()
at System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context)
at System.Web.UI.Page.ProcessRequest(HttpContext context)
at ASP.imprimerpdf_aspx.ProcessRequest(HttpContext context)
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

InnerException.Message: Unable to load DLL'ABCpdfCE6.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
InnerException.StackTrace: at WebSupergoo.ABCpdf6.Internal.NDoc._New(ManagedMethodList& methodList, StructSizeList& structSizeList)
at WebSupergoo.ABCpdf6.Internal.NDoc.New(ManagedMethodList methodList)
at WebSupergoo.ABCpdf6.Doc..ctor()
at imprimerpdf.Page_Load(Object sender, EventArgs e)
at System.Web.UI.Control.OnLoad(EventArgs e)
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

From this error, the obvious fix would be to put ABCpdfCE6.dll in the /bin directory. However, the dll is already there (after double, triple checking, all dll found on the previous working server are also on the new server).

I have tested the exact same code on various machines (both servers and development) and everything works normally so I'm pretty sure it is not directly related to ABDpdf but to some config on the new host (again, only place where it doesn't work).

I have limited access to the new host (pretty much just ftp and bad phone support) so there's some tests I wasn't able to do. During my googling to find a solution, I've come across some links but none seemed to help so far:


If anyone have an idea or can provide tips as to where to look or where to start to fix this, that would be greatly appreciated. Or maybe if there's something specific I could use to convince the host support to take a deeper look at the problem (since it's a third party dll, they refuse to go further even if the problem is probably not related directly to the use of a third party...)



Hi to everyone , i have a problem that occurred today and persist , every time i compile a program in VS2010 it just doesnt start,while if i open it via Windows Explorer it works fine   

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