A tiny bug in Service Pack 2 of MOSS 2007 and WSS 3.0 has been discovered recently. Installing SP2 changes a product expiration date and sets your SharePoint install to 180-day trial. This expiration date bug should not affect the normal function of SharePoint, at least until the expiration date passes. After 180-day trial expires, customer's data, configuration or application code will still not be affected, but will render SharePoint inaccessible for end-users.
Microsoft promised a hotfix for this bug within the next 48 hours or so (KB971620). Meanwhile, you can easily fix this problem by re-entering your license key:
- Open SharePoint Central Administration
- Go to Operations
- Under Upgrade and Migration section, click on Convert license type
- Type in your license key and hit Enter
- That's it, problem solved.