Several months ago this seemed to be a big problem. Hasn't been brought up for awhile. Try the fix below and if no solution then offer up your system details as there could be other issues.
You might also try the Forum Search Function to find more info on the LW + Vista + ZA issues.
This has worked for a few Vista users: Uninstall LW (start > all programs > LW > uninstall) & ZA. Now reinstall LW first. Finally, reinstall ZA. Installing LW before ZA seems to be the trick
Double check that the Windows firewall's off.
In LW file > disconnect. Wait 10 minutes, then file > connect.
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