Permission problem

[Pitaridis Aristotelis]

I have an application which uses an Access Database to store the various
information. It was working perfect until I had to put it in a shared folder
in order to be able to use it from various machines. Now, when I try to
execute the application, it displays the following error message:

Requsest for the permission of type 'System.Data.OleDb.OleDbPermission,
System.Data, Version=2.0.0.0, Culture=neutral,
PublicKeyToken=b77a5c561934e089' Failed.

When I click the OK Button, an other windows appears on the screen which
says:

Application attempts to perform an operation not allowed by the security
policy. To grand this application the required permission, contact your
system administrator, or use the Microsoft .NET Framework Configuration
tool.

Unfortunately I am the administrator but I have no idea how to fix it.