Note for upgrading to Acrobat Reader 5.1 for Windows

To upgrade to Acrobat Reader 5.1 from any earlier versions 
you have on your machine, you should:

1) Uninstall the old version

2) REBOOT YOUR MACHINE

3) Now install the new version

4) Another reboot is commonly recommended after installs

The reboot is a good idea to protect the Registry file.
