Windows 7 offers a nifty tool to diagnose memory errors. I’ve used it a few times across multiple laptops and to my vexation, discovered a few sticks failing. It was no wonder, therefore, why certain macros in excel refused to run, figures in spreadsheets looked off and games hung under memory intensive operations. I promptly replaced the failing chips. Now, the computers run like well-oiled engines.
Indeed, the tool is a boon, considering that it performs just as well as utilities found in costly suites like Norton Systemworks or Sisoft Sandra Professional. There is a catch however. Apparently, on some systems, (like a Compaq Core Duo I own), the computer goes on an endless reboot cycle after running the software. You’ll never even get to reach a usable desktop and the system starts up all over again!
According to some programmers, the looping of Windows Memory Diagnostic arises from configuration errors at BCD (Boot Configuration Data), a firmware-independent database for Windows Boot Manager boot-time configuration data. After the Windows Memory Diagnostic tool executes, it modifies BCD’s bootsequence entry to run {memdiag}, which thereby executes the memory tester code (memtest.exe) from the command line.
The BCD never reverts to its original form after the execution and so the bootsequence {memdiag} entry stays within BCD, thereby launching a never ending cycle of memory diagnostic tests at startup.
Correcting the error is painless. Simply rewrite the BCD to delete the bootsequence {memdiag} entry.
1. Open a elevated privilege command prompt window as administrator. It helps to deactivate the UAC temporarily.
2. Type in the following command, follow by Enter to execute the command:
bcdedit /bootsequence {memdiag} /remove
3. You’re good to go! Make sure you turn off the PC then launch it again to test the changes. If the PC reboots, you failed to save the data. Redo the steps.
Expect a lean and mean Windows 7 from here on.
