Hi Les, I too had this same or similar problem for a while. The error message I got was 'program: C:\finnigan\isodat nt\global\bin\workspace.exe - abnormal program termination - (press retry to debug program)'. This error window coincided with a lack of jump from N2 to CO2 configuration. If I clicked any of the buttons the acquisition screen terminated. If I left the screen alone the sample schedule would continue, but could receive the same error again and open a new error window. I too attempted reloads of Isodat, recalibrated the mass scale, deleted and recreated jump files, erased the entire computers hard drive and started over, and removed and replaced memory (as I always received a memory error after I closed the error message mentioned above). None of this solved the problem. I was able to narrow down the fact that the jump file was becoming corrupt for some reason after creation. Deleting and recreating this file would solve the problem for a time, but would always reoccur, however, not in a predictable number of jumps or other factors I looked at. Eventually, I replaced the computer with another that has dual processors (don't think this matters) and 1GB of RAM memory (I do think this matters). I have not seen this error message again. I am not certain that the increase in memory was the solution; perhaps the old computer had another problem within the motherboard or memory cards themselves. However, when I tried to reproduce this error on the new computer by loading the memory and processors with open programs while acquiring data I did receive an error message, however it was different, go figure (sorry did not write it down). This time the jump file was fine and did not get corrupted and once the memory was freed up again the error messages stopped. At any rate, I have not seen this error or had trouble jumping since the change in computer. I have had runs totaling 150 samples and have probably run in excess of 5000 samples so far without problem. I can dual task using internet, email, word and excel without having a problem. I realize this is not really a certified solution, but may be something to look at. If you are able to borrow a high memory system to test, it might save you the expense of buying a system that is not the solution. I any case hope this helps. If you discover the real problem I would be very interested in your findings Brian Jones Stable Isotope Ecology Lab Texas A&M University College Station, Tx. 77843-3146 979-845-8916 -----Original Message----- From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Leslie D. Price Sent: Thursday, May 04, 2006 10:35 AM To: [log in to unmask] Subject: Re: [ISOGEOCHEM] Isodat problems yes, it is when it makes the jump to CO2 that the problem arises. I will check to see if the "?" is in the window and try to see if the backup program will help. So far that has not helped. Thanks for your help, I really appreciate it! Les