Is it the case that many tables in the Access database are actually linked external references (e.g. dBASE or Excel)? Another possibility is that several users have the database open at the same time. For both cases you can solve the problem by making a simple change in the registry.
Open the program regedit.exe (using Start->Run) and navigate through HKEY_LOCAL_MACHINE to
Increase the value here for the entry MaxLocksPerFile to a number that is twice or three times (maybe even more) the current value. Thereafter the FlowHeater Definition will function properly.
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