ActiveSync after hard reset

[rgreffenius]

First off, I have to warn everyone that I'm not the most PPC literate person in the world, but I stumbled on this site a while back and it's been very helpful for me in learning.

Basically, phone (HTC Touch Diamond) had a major glitch recently and when I took it to the Sprint store, they did a hard reset. That fixed it, and they said they had restored the phone numbers to the phone. When I got home, I realized that while some phone numbers had made it back on, the vast majority hadn't. They're still on my computer, however, so I am assuming I can just use ActiveSync to restore the data, but here's the problem...

The person I spoke to at Sprint told me that the most likely problem with my phone was that something had gotten corrupted and the hard reset had fixed it - it there any chance that reloading the data using ActiveSync is going to reintroduce whatever it was that screwed up my phone in the first place? Are there any precautions I should take to minimize the chances of that happening?

Thanks in advance