Message type: E = Error
Message class:  CNV20200 - Messages for development class CNV_20200 
Message number: 761
Message text: Select end of block
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 CNV20200761, which states "Select end of block," typically occurs during data migration or conversion processes, particularly when using the SAP S/4HANA Migration Cockpit or similar tools. This error is often related to issues with the data selection or the configuration of the migration process.
Cause: Incorrect Data Selection: The error may arise if the data selection criteria are not properly defined, leading to an inability to identify the end of a data block.
Configuration Issues: There may be misconfigurations in the migration settings or parameters that prevent the system from processing the data correctly. Data Integrity Issues: If the data being migrated has integrity issues (e.g., missing references, incorrect formats), it can lead to this error. Technical Limitations: The system may have limitations regarding the size or structure of the data blocks being processed.
Solution: Review Data Selection Criteria: Ensure that the data selection criteria are correctly defined. Check if the start and
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
CNV20200760 Select start and end of block
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNV20200643 Cash journal business transaction mapping generated. No action required.
What causes this issue?  Based on the given company code mapping (merge of company codes) it is checked if existing cash journal business transactions...
CNV20200762 More than two lines were selected; select start and end of block
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNV20200791 __with parameters: IMMED=&1, START=&2, DATE=3, TIME=&4
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.