install anytime upgrade

Is it necessary to back up files and programs prior to doing upgrade from home premium to professional ??

Gentlemen---thank you for responding but----I did it with no problems. I have a new HP9300 quad that came with 7 home premium. I bought the anytime upgrade and from what I read in this forum, this is merely a key to unlock what was already there not a download at all..Had I been familiar with the nuances of the various programs I would have started with 7 pro initially. I think for backing up I'll get an external hard drive or learn how to back up files only on DVD. I made the recovery disc's early on which is new to me. Used to get actual disc's to be able to re-install the program in olden days. Now, you make your own. Talk about pinching pennies. I won't go through the mantra of damning MS---got to appreciate what we have at our disposal today---I remember the punch cards initially. Also remember when a 40 megabite hard drive was a big deal.

Thank you for your comments. Want to add at this point that my HP 9300 does not have a V chip so the upgrade was and is a waste of money. Again, being grateful for what we have is hard to do when MS continues to diddle you. I won't waste time talking about customer service---we all know what "service" is if we have any farm background.

To Carl S............what type external hard drive do you use ? I assume it's a USB hook up. Is it one of the self powered units or an enclosure with full sized HD ?

One thing to keep in your mind,is if you need to use the OEM Recovery Partition, this will only reinstall Home Prem.