Newbie: Access denied error when using impersonation

[Navin Mishra]

I've written a simple web service in which I'm accessing some DLLs. When I
run it, I get following error:

CS0009: Metadata file
'C:\WINDOWS\Microsoft.NET\Framework\v1.0.3705\Temporary ASP.NET
Files\testwebservice\2c51778e\c9520a07\assembly\dl2\471bace8\80eba47e_cd1fc3
01\IDLibrary.DLL' could not be opened -- 'Access is denied. '

I'm using impersonation because it is required to access a database from a
referenced DLL. But it is not going upto that point at all.

Any help is appreciated!

Thanks in advance and regards

Navin