Errors with Application Servers

Hi all, I have problem with Navision Application Servers when installing Commerce Portal. Both Application Servers return error messages: nas: “The operating system cannot gain access to the file . Please check that the file type and attributes are correct.” nassql: “The CommercePortal_commerce database on the S2003 server does not contain Microsoft Navision Attain system objects and cannot be opened.” Where could be problem?