Welcome to the board.

We have verify your code and it should work correct, but it is possible that
during the logon phase you can't remove this value.
We have extend your code to see what is happening.
Please run it and return the result on the board.

code:

---

? "Actual  Username:       "+@userid
? "        Registry value: "+ReadValue("HKEY_LOCAL_MACHINE\Network\Logon","username")
IF (DelValue("HKEY_LOCAL_MACHINE\Network\Logon","username") <> 0)
  ? "Status removing value: @error (@serror)"
ELSE
  ? "Status removing value: no error"
ENDIF
? "Current Registry value: "+ReadValue("HKEY_LOCAL_MACHINE\Network\Logon","username")

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