I am trying to compile a dll to a remote server but keep getting the
above error message.

The problem is not with the actual assembly I am building (because
that doesnt yet exist), it is with all the referenced dll's.
They are all currently in the directory \\server\dir which I am
building the new project to. Hence I guess it is trying to overwrite
them, with exactly the same files.

Permissions on the directory are ok, both the local user and ASP.NET
user have got full access to all files/directories
.
Ideally the files in questions (which are purely reference dll's) can
just remain where they are, they shouldnt need overwriting at all in
the first place.

Any ideas?