Sage Line 50 Accounting never uninstalls completely and occasionally on upgrade will stop working with such sypmtoms as:

1. When sage is run it hangs on the splash screen
2. when Sage is run and then a company is selected it hangs on the splash screen

To solve this follow these steps:

1. Uninstall .Net Framework 2.0
2. Uninstall Sage
3. Goto C:\Program Files\Common Files and delete all sage folders
4. Delete C:\WINDOWS\sage.ini
5. Move/Delete C:\WINDOWS\SYSTEM32\sg*.* (I also turn company on in details and check for any further Sage files)
6. Rename Sage program directory, all data files are maintained here
7. Reboot PC
8. Install .Net Framework 2.0 of the Sage CD
9. Install Sage of the Sage CD
10. Reboot

Sage should now work. You can now also install any company data in to Sage. I would also install all updates.