Sharepoint 2007 problem

Hi!

We are running SBS2008 along with the version of Sharepoint 2007 that accompanies it. Recently we upgraded all our clients to Windows 7, and everyone is reporting problems with the "check out" feature of the document libraries, as well as the explorer view. They just get an error. On my xp machine it works fine.

I have installed all updates on the server, but they still get an error.

The problem seems to be related to office documents only since pdf files check out nicely. We run office 2007 standard.

We get the error "object reference not set to an instance of an object", and I ahve tried all troubleshooting such as

http://kbalertz.com/833714/requires-...t-library.aspx

without any success...

/Henrik