Problem with "add reference" under Visual C# 2008 Express Edition after switching from XP to Windows 7

Question

Hello everybody,

I suddenly have a big problem I didn't have before.

In my current project, I want to add a reference to "Microsoft.Office.Interop.OneNote". When I open the .NET tab of the "Add Reference" dialog, the "Microsoft.Office" assemblies aren't available like they used to be; on my machine, the next assembly after "Microsoft.JScript" is called "Microsoft.SqlServer.ConnectionInfo"; no trace of any of the "Microsoft.Office" assemblies. I used to be able to do this under Windows XP, but made the switch to Windows 7 a couple of weeks ago. I don't know whether that has anything to do with it.

I already checked whether the assemblies are installed on my machine, but I found all of the office assemblies safe and sound in "windows\assembly". Oddly enough, the reference to "Microsoft.Office.Interop.OneNote" in a previous project continues to work; I just can't add any new references with the "add references" dialog, as they aren't shown in the list of .NET references anymore.

Any help will be appreciated.

Kind regards,

Rainer

Answer 1

Pardon the perhaps stupid question.

Have you installed MS Office since you switched from XP to windows 7?

I'm only asking because I forgot to install it after the same upgrade and I spent a good half hour last week trying to figure out why my project that used Powerpoint was complaining.

Answer 2

Hi,

the content of the dialog you see with ´Add Reference´ is actually not loaded from the GAC. It´s some registry-folder settings for visual studio.

Maybe you installed in such a way that the libraries are not part of this set. Then VS will not show them in the dialog.

for more info on how to add entries to your ´add reference´ dialog see

http://support.microsoft.com/kb/306149

Answer 3

I think I have got it. For the benefit of anyone who runs into the same problem, there was an interesting lesson to be learned about some lesser known features of Windows:

The link Marvin mentioned above...

http://support.microsoft.com/kb/306149

...says:

To display your assembly in the Add Reference dialog box, you can add a registry key, such as the following, which points to the location of the assembly

[HKEY_CURRENT_USER\SOFTWARE\Microsoft\.NETFramework\AssemblyFolders\MyAssemblies]@="C:\\MyAssemblies"

where MyAssemblies is the name of the folder in which the assemblies reside.

So I did just that, replacing "myAssemblies" with "C:\Windows\Assembly".

Nothing happened.

I changed the value of the empty standard key to "C:\Windows\Assembly".

Nothing.

I tried some variations of the theme: double backslashes, ending with a backslash, the return of the son of the backslash. No cigar.

So I tried to work the other way around by trying to copy the necessary dll from c:\windows\assembly into one of the directories that are being watched by the "add reference" dialog. On my machine, these paths are conveniently listed under

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft.NETFramework\v2.0.50727\AssemblyFoldersEx]

When I tried to copy the dll from c:\windows\assembly, there was no "copy" option in the context menu. Drag'n'drop didn't work either. For this problem, I found several alternative solutions here:

http://geekswithblogs.net/pavelka/archive/2006/05/05/WindowsExplorerAndTheGlobalAssemblyCache.aspx

I opted for solution 2:

Add DisableCacheViewer Registry Key Another way to disable to create a new dword key under HKLM\Software\Microsoft\Fusion\ with the nane DisableCacheViewer and set it’s [DWORD] value to 1.

After I had done that, I could see the real directory structure below c:\windows\assembly; almost each and every dll has its own subdirectory. As soon as DisableCacheViewer was set, I could

• traverse the real directory tree that was hidden under c:\windows\assembly
• copy dlls and paste them to one of the directories listed under "AssemblyFoldersEx"
• deduce the correct path to my dlls and create a fresh key to that path just below "AssemblyFoldersEx".

Thank you very much to everyone who answered, and a special thanks goes to hannes pavelka, whose blog entry helped to solve my problem.

P.S.: I'm almost certain that I never had to do this under Windows XP. IIRC, all of the interop assemblies were available without this kind of registry fumbling.