Created Issue: Unspecified error when pasting in solution explorer across VS instances [847]

Beta build

Start instance #1 of VS, create an Azure Express project
Start instance #2 of VS, create (NON-Azure) Express project

In solution explorer of instance #1, multi select `bin`, `web.config`, `web.Debug.config` and CTRL-C copy.
In solution explorer of instance #2, CTRL-V paste.

Result:
```
---------------------------
Microsoft Visual Studio
---------------------------
The operation could not be completed. Unspecified error
---------------------------
OK
---------------------------
```


If you just try to copy one file instead, you'll get a different error:
```
---------------------------
Microsoft Visual Studio
---------------------------
The source URL 'Web.config' could not be found.
---------------------------
OK
---------------------------
```