Message type: E = Error
Message class:  CNV_PE - General messages for posting engine 
Message number: 488
Message text: Execution rule step must be provided
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 CNV_PE488 indicates that an execution rule step is required but has not been provided in the context of a data migration or conversion process. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: The error occurs when: A required execution rule step is missing in the configuration of the migration or conversion process. The execution rules that dictate how data should be processed during the migration are not properly defined or are incomplete. There may be a misconfiguration in the migration project settings or the specific migration object being processed.
Solution: To resolve the CNV_PE488 error, you can take the following steps: Check Execution Rules: Go to the migration project or the specific migration object where the error occurred. Ensure that all necessary execution rules are defined. This may involve reviewing the configuration settings and ensuring that all required steps are
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
CNV_PE487 Dynamic DB select in table &1 failed
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNV_PE486 Grouping is not supported for an execution rule with multiple steps
What causes this issue?  A transfer method is assigned to an execution rule with multiple steps. That means at least one further transfer method is as...
CNV_PE489 Execution rule step &1 is ignored
What causes this issue?  The execution rule step &V1& is not executed as the <ZK>Ignore </>transformation rule of the correspondin...
CNV_PE490 Not allowed to change execution rule step
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.