Novell Client 2 for Windows
After locking the workstation, when attempting to unlock, no password field is visible, and the user cannot unlock the machine.
Delete the "C:\ProgramData\Microsoft\User Account Pictures\user.bmp", and then copy one from a machine that works. Verify the file permissions are correct.
The Novell Client first checks for the presence of a user-defined bitmap, then if none is found, uses Microsoft's default user bitmap in "C:\ProgramData\Microsoft\User Account Pictures\user.bmp". If that file does not exist, the Novell Client resorts to using a default bitmap embedded in the Novell Client Credential Provider (NCCredProvder.dll).
The Novell Client Credential Provider log is useful in identifying this problem.