2587238 - How to disable Personas to prevent syntax errors on SAP GUI

The syntax error occurred after updating SAP Screen Personas Support Packages (SPs) into the system.

In order to check the system's status or implement the corrections, you need to disable Personas temporarily to get rid of the syntax error during SAP GUI logon.
You have tried many ways to disable Personas as explained in SCN: Deactivating SAP Screen Personas, following symptoms still could be observed:

• Syntax error occurs during SAPGUI logon even though you have set DISABLE_WINGUI with value X in transaction /n/PERSONAS/SETTINGS.
• Via R/3 connection (to check the system as a remote support engineer), syntax error occurs during SAP GUI logon even though the support engineer has set "/SUPPORTBIT_OFF=SAP_PERSONAS" or the corresponding Windows Registry on his/her local SAP GUI.

Personas 3.0 SP4 or above

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