Message type: E = Error
Message class:  CNVOM_DEL_CHECK - Messages for Deletion Check 
Message number: 018
Message text: Task existing for table &1 while its parent table is inactive
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).
Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.
You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.
The SAP error message CNVOM_DEL_CHECK018 indicates that there is a task existing for a specific table (denoted as &1) while its parent table is inactive. This typically occurs in the context of data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools.
Cause: Parent-Child Relationship: The error arises when there is a dependency between tables, where the child table (the one mentioned in the error) cannot be processed because its parent table is not active or has not been properly initialized. Data Migration Issues: This can happen during data migration when the sequence of processing tables is not followed correctly, leading to inconsistencies. Configuration Errors: There may be configuration issues in the migration settings that prevent the parent table from being activated.
Solution: Check Parent Table Status: Verify the status of the parent table. Ensure that it is active and properly initialized before attempting to process the child table. Activate Parent
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
CNVOM_DEL_CHECK017 Check is object independent
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNVOM_DEL_CHECK016 No deletion task
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNVOM_DEL_CHECK019 Invalid deletion tasks existing for inactive data set '&1'
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNVOM_DEL_CHECK020 Deletion Tasks for &1
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
Click on this link to search all SAP messages.