Access X509Certificate Store from ASP.net 2.0

[Ash]

Hi,

I have coded a c# dll which accesses my certificate store retrieves a
certificate and signs some xml using the SignedXml class.
I wanted a webservice to access this dll and provided a web interface for
it, however when attempting to sign the xml i get an exception:

CryptographicExceptin: Keyset does not exist

This exception is raised when i try to access the private key of the
X509Certificate2 class.

My certificates are stored in a separate container with the Local Machine.

I run a small console application and it works fine, so i am assuming that
asp.net is having trouble with doing this.

Thanks

Ash