MOSS "trial period for this product has expired"

Recently I faced an strange issue related to MOSS. One of my content admin is complaining that he is unable to add any link or page in his site anymore. whenever he is trying to create any page he is getting this error

"trial period for this product has expired"

Our MOSS farm has correct license and we haven’t upgraded MOSS from trial version. After thorough analysis and research, I found that there is a bug in MOSS SP2 which reinitializes the license file and turns MOSS normal license to 180 days trial  license.

For fixing this issue, you can go to MOSS central admin->operations->Convert license type->Enter product key and add the key again or apply the hotfix mentioned in the below KB article.

http://support.microsoft.com/kb/971620

Downloadable contents for Office SharePoint Server 2007

Microsoft is providing lots of books, white papers and articles on MOSS configuration and deployment for free. We as a MOSS consultant use these resources in most of the projects as a baseline for architecture. Below link contains a complete list of all downloadable contents available on MOSS, this list is continuously updating by Microsoft for covering new versions and service packs;

http://technet.microsoft.com/en-us/library/cc262788.aspx