I have just released a new version of SETI Driver (v1.6.4.1) that has an
additional option to have SETI Driver override the CLI's insistance at
running at priority level 4.  This option forces the client to run at
priority level 1 (when combined with "Low"), which is as low as you can go
on Windows.  Note that the WIndows GUI client does this when its running in
background.  This should fix the lockups in Windows XP and Outlook 2000 and
later when using the off-line folders features of these products.

The command line switch is -runidle and is saved in the configuration file
during a Save Config.

Mike Ober.
http://www.wakeassoc.com/setidriver/setidriver.zip