How To Fix SMT156 - Only letters and the special character "_" are allowed for mappings

SAP Error Message - Details

• Message type: E = Error

• Message class: SMT -

• Message number: 156

• Message text: Only letters and the special character "_" are allowed for mappings

Self-Explanatory Message

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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