Message type: E = Error
Message class:  CNV_CDMC_CA - CDMC Clearing Analysis 
Message number: 146
Message text: User & is already editing the display of the project &
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The SAP error message CNV_CDMC_CA146 indicates that a user is already editing the display of a project in the SAP system. This typically occurs in the context of the SAP Conversion Management (CDMC) tool, which is used for data migration and conversion projects.
Cause: Concurrent Access: The most common cause of this error is that another user is currently accessing or editing the same project. SAP does not allow multiple users to edit the same project simultaneously to prevent data inconsistencies. Session Timeout: If a user was editing a project and their session timed out, the lock may not have been released properly, causing the system to think that the user is still editing the project. System Lock: Sometimes, system locks can occur due to various reasons, such as a crash or improper logout.
Solution: Check Active Sessions: Verify if another user is indeed editing the project. If so, you may need to wait until they
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