Hello I thought I would pass along my excellent adventure..... We are running WinXP Isodat 2.0 for a Delta EA system. I downloaded and installed the WinXP SP2 update since it is a critical patch. This lead to some issues and I was wondering if anyone has seen any problems doing this. While I could still control everything through the Aquisition window, when I used the Instrument control window I had no response from the Conflo Ref1/Ref2 at all. The system would also crash during the final steps of a Mass Calibration. I am not sure if the SP2 patch is causing problems with Isodat 2.0 directly (blocking communication with the spec), the National Instruments GPIB Card or the Dell computer this is running on. I would get various Microsoft error report messages which provided reams of Techno gobble-de-goop - but no real insight as to what was happening. Opening the new Microsoft Security window caused a total computer lock-up. Other WinXP (non-mass spec, non-Dell) workstations have patched just fine with no problems. I have since rolled back the SP2 update and all Isodat functions seem to be back to normal. I haven't been able to find any word on using or avoiding the SP2 patch anywhere, so I am curious to hear from anyone out there regarding Isodat 2.0 or the WinXP Masslynx 4. Cheers, Bill Mark Isotope Technician Environmental Isotope Lab University of Waterloo Phone (519)-885-1211 Ext 6747 FAX (519)-746-0183 http://sciborg.uwaterloo.ca/research_groups/eilab