Access Violation in SPOOLSS when Printing to a Serial Printer

• Microsoft Windows NT Workstation version 4.0
• Microsoft Windows NT Server version 4.0

SYMPTOMS

If a serial port configuration string greater than 20 characters is specified and that serial port is used by an active printer, Localmon.dll generates an access violation in Spoolss.exe.

CAUSE

This problem can only occur if the following Registry Key is directly edited using a Registry Editor:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\
CurrentVersion\Ports\COMx

If a serial port configuration string greater that 20 characters is entered into this value it will cause Localmon.dll to generate an access violation.

These keys are normally directly configured using Ports in Control Panel. If this application is used, it is not possible to specify a port configuration greater than 20 characters. However, it may be necessary to specify a custom port configuration for some serial handshaking options, which can require a string longer than 20 characters.

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Additional query words: prodnt GPF General Protection Fault CPL AV

Keywords : kbnetwork ntprint kbfix4.00.sp3 NTSrvWkst
Version : 4.0
Platform : winnt
Issue type : kbbug