I upgraded to the device software of v 4.5. When I did my first sync to my PC Outlook calendar it deleted everything from the upgrade forward. Calendar on the BB is fine. When I sync'd got the message that it was deleting, assumed it would re-add like it did during the upgrade, but it did not. I have a Curve 8300. Ideas?

After the upgrade, was every restored or was the calendar blank after the upgrade?

You can restore all your data from an old backup and then run the sync again and do a "re-sync" that should get everything going.

When you update your BlackBerry their should be a LoaderBackup(Date).ipd file somewhere on your computer, so search for "*.ipd" and restore the latest backup and then do a re-sync, that should get your BB back to normal..

Are all you calendar events still in Outlook?

Everything restored OK on the BB, just took everything out of Outlook from the upgrade date forward. I'm thinking a file location changed somewhere but can't figure out where.

I would reset and re-configure the sync in the desktop. Especially if nothing is in Outlook but everything IS on your BlackBerry, then run the sync again.