Here is what the manual says about the user count. I have never seen a negative user count myself but it sounds like there might be a problem with the runtime. Have you talked to Acucorp about it?
Ted
A value of note is the "user count". This value starts at zero, and is incremented each time the file is opened for I/O. This number is decremented when the file is subsequently closed. Under normal circumstances, the user count indicates the number of users who are currently updating the file. Should runcbl die suddenly, then this number will not be decremented. Thus, if the user counter is ever non-zero when there are no users active, then it indicates a sudden program failure and suggests that corrective action may need to be taken. At the very least, the file should be checked for integrity, but depending on the program that died, perhaps more significant action should be taken.
Basically a non-zero user count indicates that someone knowledgeable about the system should intervene and ensure that everything is okay. This can be used as an early warning system to head off some problems before they surface in a more serious form. Note that under normal operation, a COBOL coding error will not cause this condition to occur, because runcbl will usually close all of its files when it detects an error.