Message type: E = Error
Message class:  E_ACTION - E-Actions 
Message number: 171
Message text: Invalid 'Regular Expression'. Please enter correct 'Regular Expression'.
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The SAP error message E_ACTION171 indicates that there is an issue with a regular expression that has been entered in the system. This error typically arises when the regular expression syntax is incorrect or does not conform to the expected format.
Cause: Syntax Error: The regular expression may contain invalid characters or incorrect syntax. Unsupported Features: The regular expression may be using features that are not supported by the SAP system. Misconfiguration: The regular expression might be intended for a different context or application, leading to incompatibility. Escaping Issues: Special characters in the regular expression may not be properly escaped.
Solution: Check Syntax: Review the regular expression for any syntax errors. Ensure that it follows the correct format for regular expressions. Test Regular Expression: Use a regular expression testing tool or online regex tester to validate the expression before entering it into SAP. Refer to Documentation: Consult the SAP documentation for the specific context in which the regular expression
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