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By default, SAP NetWeaver Application Server (SAP NetWeaver AS) ABAP enables you to use a wide variety of unicode characters for user names. This freedom results in a number of undesirable results:

  • Invisible names that consist of spaces and non printable control characters

  • Names written with characters from different alphabets, but appear to be identical


    With the unicode values of characters drawn from the Latin, Greek, and Cyrillic alphabets, you can create the same user multiple times. The following entries result in two users with the name MITTE

    • 1C04 4900 2204 A403 4500

    • 4D00 4900 5400 5400 4500

    The users appear to have identical names, but the unicode values for the character differ.


We recommend that you limit the characters that SAP NetWeaver Application Server ABAP uses for user names. To limit characters for user names, you must customize your SAP NetWeaver AS.


Open table PRGN_CUST in Maintain Table Views (transaction SM30) and maintain the parameter BNAME_RESTRICT.




We recommend this value. This configuration is the most restrictive. You can only use the following characters in user names and no others.



This configuration limits where in user names you can use spaces and control characters: F (ront) M (iddle) E (nd). To disallow spaces or control characters, replace F, M, or E with an X.


XME means you cannot begin a user name with a space or a control character. FXX means you can only include a space or control character at the beginning of a user name. XXX means that user names cannot include spaces or control characters.

This configuration does not limit the use of any other characters in user names.


No restrictions. Use this configuration to maintain compatibility with older releases.

To use the old user management transactions SU01_OLD and SU10_OLD, you must use this option.

More Information

SAP Note 1731549 Information published on SAP site