There are umteen posts about the troubles we all have with Windows Mobile 5 and Activesync 4.x. I have my Axim X51v set up to Sync via USB and not the funky network emulation that is the default (set in Settings/Connection/USB to PC on the PDA). This workaround pertains to when Windows detects the hardware (i.e. the device does show in Device Manager) but Activesync doesn't activate. I noticed that when I take the PDA out of the cradle and then run the connection wizard in Activesync, the wizard would make the successfully detected sound if I placed the PDA back in the cradle during the detection phase.
So I thought, well Windows sees it, Activesync sees it, but the PDA never displays the "Connect To" progress indicator that shows up when the PDA syncs successfully. So I looked through the Windows directory on the PDA and I found that if I run repllog.exe Activesync will initiate on both the PDA and the PC and I get a sync. After this it seems to work even after soft-reset until I try to sync with another PC.
So, if you make a shortcut to the repllog.exe and place it somewhere that you can easily get to it, this might work for you too. I hope this helps relieve someone's frustration as it did for mine
So take a deep breath - in with the butterflies out with the bees - and relax so you can get back to the many other frustrations of life. Your PDA should not be one of them.
JaMMy