Unidata 8.2.1 on RHEL - what does this error mean? When it happens the system usually locks up (when udt is started from the .profile) and people can't login until Unidata is forced down with stopud -f and restarted.

Kevin,

A upl_unlock error occurs when UniData cannot free a resource from it's lock table, it can be a toggle / latch, record lock, file lock or semaphore  and can occur for several reasons, there is an internal tool we can use to examine the lock table and see if this is something like a stuck toggle that can be released or something more serious such as lock table itself becoming corrupted. I know in our previous conversations you've stated you don't have a support contract with Rocket yourself. If the company you are working with does have a support contract then with this type of issue it really does need to be looked at by Rocket Support as this could be a product bug leading to the problem. We do know of situations where a stuck toggle can lead to the situation you describe and we are currently looking into the root cause of this but we would need to examine the lock table to find out. If it is a stuck toggle we can show you how to identify it and how to unlock it with a hidden option in the internal tool. 

Given the potential nature of this type of error it really is best discussed in a support case and not on the forum.

Thanks,
Jonathan

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