I cannot add an `Additional Assembly` (DLL) via my Event Receiver Package settings. When I attempt to deploy, I get the following error:

```
3>  Deploying solution 'EventReceiver.wsp'...
3>Error occurred in deployment step 'Add Solution': Error: Cannot add the specified assembly to the global assembly cache: ExampleLibrary.dll.

```

Also, I can manually install the DLL to the GAC (using Gacutil) and it works fine in a test Windows Forms application. However, if I register the assembly details in the SharePoint Web.config in the `<compilation` section, I get the following error:

`Parser Error Message: Could not load file or assembly 'ExampleLibrary, Version=4.6.0.0, Culture=neutral, PublicKeyToken=XXX' or one of its dependencies. The system cannot find the file specified.`

I image the issues are related - what could be the problem here?

If I use the provided .NET 2.0 versions of the DLL it still fails. Checking the DLL with `CORFLAGS` shows the following:

```
Version   : v2.0.50727
CLR Header: 2.5
PE        : PE32
CorFlags  : 0x9
ILONLY    : 1
32BITREQ  : 0
32BITPREF : 0
Signed    : 1

```

... so it doesn't appear to be a 32-bit issue. How can I resolve this?