Ultimate PC Troubleshooting Guide

Step-by-Step: Battle the Enigmatic Blue Screen of Death

It's big, it's blue, and it fills your screen--the infamous Windows General Protection Fault. If you get GPFs often, your PC may have two or more DLLs slugging it out. Have no fear. Grab your gloves and safety goggles, and we'll dig into Windows and see what's causing the trouble.

1. Uninstall that new program. If your PC crashes or locks up after you install a new program, uninstall it; your computer may return to normal.

2. Check the DLLs. Dynamic link libraries are small programs used--and often shared--by many Windows applications. First look for duplicate DLLs, compare the versions, then get rid of the old ones. Follow these steps.

From the Windows desktop, press F3, which brings up the Find: All Files box (or the Search Results box in Windows Me). Make sure Include subfolders is checked (Advanced Options and Search Subfolders in Windows Me) and the 'Look in' field shows My Computer, then type *.dll in the 'Named' field. The results window will be jammed with files. Sort them by selecting View, Details and clicking the Name column heading.

Search tip: To ease your search, first look for DLLs that cause the most trouble, which are usually files that begin with the following letters: BWCC, CO, CTL, MFC, MSV, and OLE. Use the "wild card" trick and add *.dll after each set of those letters. For instance, typing MFC*.dll will find all DLLs that start with MFC.

3. Compare and zap the duplicates. To do this, right-click each duplicate file, select Properties, and click the Version tab. Then compare the versions (and I'll bet files with higher version numbers will be in the Windows System folder). Remember: The date isn't important--it's the version number that is critical.

4. Rename the DLLs. If you discover a DLL with a lower version number in an application's folder and in the Windows System folder, don't delete it. Instead, highlight the file and press F2 to rename the file extension to .d_l. Doing so keeps the old DLL version from loading and forces the program to look in the System folder for the right DLL. After each DLL renaming ceremony, reboot your PC. If all's well, rename more old DLLs.

Shortcut: Download a copy of DLL Checker, a shareware program that finds and highlights duplicate DLLs; it makes renaming DLLs quick and easy.

--Steve Bass