Message type: E = Error
Message class:  AQV - Message texts for SAP Query 
Message number: 518
Message text: Specify a number of characters
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.
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The SAP error message AQV518 ("Specify a number of characters") typically occurs in the context of data entry or configuration where a character limit is expected but not provided. This error can arise in various scenarios, such as when defining text fields, entering descriptions, or configuring certain parameters in SAP.
Cause:
Missing Input: The user has not specified a required number of characters in a field that expects a certain length.
Field Configuration: The field may be configured to require a specific number of characters, and the input does not meet this requirement.
Validation Rules: There may be validation rules in place that enforce character limits, and the input does not comply.
Solution:
Check Input Fields: Review the input fields where the error occurred and ensure that you have entered the required number of characters. If a minimum length is specified, make sure to meet that requirement.
Field Length Configuration: If you are configuring a field, check Get instant SAP help. Sign up for our Free Essentials Plan.
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