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The lock was caused by a faulty transport (e.g. return code 12). In this case, the system queue was blocked for security reasons, based on the threshold value maintained in the global settings.
After a database copy, the error message "TM system has been reset" appears in the Import Scheduler Monitor and all queues are blocked.
Inconsistent entries in the table / RTC / TM_SCTM on the TM server and target system caused by:
An aborted RFC connection to the TM system while a job is running
Different system times for TM server and target system
Solution
Re to 1.: Check the faulty transport and make the necessary adjustments.
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