WiFi Problem after Syncing with PC

[Guest adjonline]

I'm trying to deal with an annoying problem with my Vario III. After I physically (USB) sync my device with my Vista computer, I can no longer connect to any wifi network. The phone still says wifi is enabled, but it doesn't actually seem to be. It won't, for example, show up the screen from which one can select the preferred network. The only way I can get back onto wifi is to soft reset this phone. What's more, the problem has persisted after a hard reset. I am running the T-Mobile ROM with which it shipped.

Any ideas?!