We are having a problem linking an assembly produced by Visual Studio 2005 to
an existing Excel 2003 spreadsheet (.XLS) file. (The assembly is correctly
linked to the Excel 2003 spreadsheet created by the Visual Studio 2005
project.)

With Visual Studio 2005 and Microsoft Visual Studio 2005 Tools for Office
2007 SE we have successfully built an install project that deploys a strongly
named assembly ExcelWorkbookSimple.dll with ExcelWorkbookSimple.xls. This
"app" just puts up a simple ActionPane. The ExcelWorkbookSimple.xls file can
be copied anywhere and works -- starting the ActionPane -- as long as the
installed directory containing ExcelWorkbookSimple.dll is available and has
not been renamed.

We have tried adding the AssemblyLocation / AssemblyName custom properties
using Excel and Windows Explorer with no success. Each time we get the
following message:

"The current .NET security policy does not permit
ExcelWorkbookSimple to run from the folder C:\The\Actual\Path\.
Do not change the security policy in your computer. The .NET
security policy is controlled by your administrator or the
developer who wrote the custom macros. You can still edit and
save the document. Contact your administrator or the author of
this document for further assistance."

We are not trying to reference a LAN / network location, nor are we trying
to access a web location. We are trying to access a folder on the same
computer.

We tried

_AssemblyLocation0 = C:\The\Actual\Path\ and C:\The\Actual\Path
_AssemblyName0 = ExcelWorkbookSimple

and

_AssemblyLocation = C:\The\Actual\Path\ and C:\The\Actual\Path
_AssemblyName = ExcelWorkbookSimple

from both Excel and Windows Explorer.

caspol -lf did not initially show ExcelWorkbookSimple.dll had full trust.

caspol -rsp ExcelWorkbookSimple.dll showed the following before
and after adding full trust:

Microsoft (R) .NET Framework CasPol 2.0.50727.42
Copyright (c) Microsoft Corporation. All rights reserved.

Resolving permissions for level = Enterprise
Resolving permissions for level = Machine
Resolving permissions for level = User

Grant =
<PermissionSet class="System.Security.PermissionSet"
version="1"
Unrestricted="true"/

Success

Granting full trust worked as follows:

C:\The\Actual\Pathcaspol -af ExcelWorkbookSimple.dll

Microsoft (R) .NET Framework CasPol 2.0.50727.42
Copyright (c) Microsoft Corporation. All rights reserved.

Because all GAC assemblies always get full trust, the full trust list is no
long
er meaningful. You should install any assemblies that are used in security
policy
y in the GAC to ensure they are trusted.
The operation you are performing will alter security policy.
Are you sure you want to perform this operation? (yes/no)
yes
Success

caspol -lf after granting full trust showed the assembly:

Microsoft (R) .NET Framework CasPol 2.0.50727.42
Copyright (c) Microsoft Corporation. All rights reserved.

Security is ON
Execution checking is ON
Policy change prompt is ON

Level = Machine

Full Trust Assemblies:

....

22. ExcelWorkbookSimple 1.0.0.0 =
StrongName -
00240000048000009400000006020000002400005253413100 04000001000100E7D33901080D61DBD1F68A4A9432F633B282 33AB9572BA75763EAF9B59894EA45D36303BD2CB7669052E05 08A2EB0C30BAE44E1A49FF43ECC978C100DB42E8A021F66A80 F0B35668C8A44DFC5795349AC8C9FCC245FECDB539A964A059 544CF2A9A67DE13D6C05A84DB31E36A9031772426E2DC5A1D8 A6019F862F5762D176D4 name = ExcelWorkbookSimple version = 1.0.0.0
Success

Even after granting full trust we still get the same message.