If you are on iMac with SnowLeopard, with a new iPhone4s, installed Documents To Go (basic ed), managed to get it to connect once and synchronized some files to your phone, but could not re-sync when you left the house and returned, here is a workaround:
Close Documents To Go Desktop,
Restart your iMac
Open Documents To Go Desktop
Open Documents To Go on iPhone
On iPhone4s:
Navigate to "Desktop Accounts"
Click on the listed desktop
Press the "Sync" circle at bottom left of display
Celebrate briefly (because you will have to repeat whole process shortly)
Close Documents To Go Desktop,
Restart your iMac
Open Documents To Go Desktop
Open Documents To Go on iPhone
On iPhone4s:
Navigate to "Desktop Accounts"
Click on the listed desktop
Press the "Sync" circle at bottom left of display
Celebrate briefly (because you will have to repeat whole process shortly)