How soon after startup does it close down? Do you have time to go to the options & change any settings. I'd suggest you set it for manual connect.
But 1st it might be an idea to delete the LW Preferences folder called
.limewire (whilst LW is closed!) & found here:
Windows NT 4.0 / 2000 / XP: C:/Documents And Settings/your_username/.limewire
OR Windows 98 / ME: Your .limewire folder is in "C:\My Documents" (BUT make a note of all your LW settings 1st, b/c after you delete the LW prefs folder you'll need to reset them.)
Infact I'd suggest you run thru these checks:
Fixes for Limewire