Windows Memory Diagnostic checks your RAM for errors, which can cause crashes, blue screens, freezing, and corrupted files. The catch is that after the test finishes and Windows restarts, the results may flash by in a notification, or not appear at all. They are saved in Event Viewer, and this guide shows exactly how to find them, what the results mean, and what to do next.
Quick Answer
Right-click Start and open Event Viewer. Go to Windows Logs > System, click Filter Current Log in the right pane, choose MemoryDiagnostics-Results from the Event sources list, and click OK. Open the newest event (usually Event ID 1201) to read the result.
Step 1: Run the Test (If You Have Not Yet)
- Save your work and close apps.
- Press Windows key + R, type mdsched.exe, and press Enter. Or search for Windows Memory Diagnostic.
- Click Restart now and check for problems (recommended).
- The PC restarts and runs the test. It can take several minutes to over an hour, depending on how much memory you have and which test mode is used.
- Windows restarts automatically when the test is done.
While the test runs, you can press F1 to change options, such as the Extended test mix for a more thorough check.
Step 2: Find the Results in Event Viewer
- Right-click the Start button and choose Event Viewer (or press Windows key + R and type eventvwr.msc).
- In the left pane, expand Windows Logs and click System.
- In the right Actions pane, click Filter Current Log.
- Open the Event sources dropdown, check MemoryDiagnostics-Results, and click OK.
- Double-click the most recent event, or read the General tab below the list.
Alternative: click Find in the Actions pane and search for MemoryDiagnostic.
What the Results Mean
| Event ID | Message (summary) | Meaning |
|---|---|---|
| 1201 | Tested the computer's memory and detected no errors | RAM passed. Memory is unlikely to be the cause of your problem. |
| 1202 | Tested the computer's memory and detected hardware errors | RAM failed. One or more memory modules may be faulty. |
| 1101 / 1102 | Test scheduled or started | Informational only. Look for the 1201 or 1202 result event. |
Check Results With PowerShell
Open PowerShell and run:
Get-WinEvent -FilterHashtable @{LogName='System'; ProviderName='Microsoft-Windows-MemoryDiagnostics-Results'} | Select-Object -First 5 TimeCreated, Id, Message
This lists the most recent results with dates.
If the Test Found Errors
- Reseat the RAM: shut down, unplug the PC (and remove the battery if possible), and firmly reseat each memory stick. On many laptops, RAM is soldered and cannot be removed.
- Test one stick at a time: on desktops, remove all but one module and rerun the test to find the faulty stick.
- Reset overclocking: if you enabled XMP/EXPO or memory overclocking in BIOS, set it back to default and test again.
- Run a second test: a more thorough third-party tool such as MemTest86 (run from a USB drive) can confirm the result.
- Replace faulty RAM: contact the manufacturer if the PC is under warranty.
If No Errors Were Found but Problems Continue
- Run the test again using the Extended mode.
- Update drivers and Windows.
- Check your drive health and run
sfc /scannowto repair system files. - Look at other errors in Event Viewer or blue screen codes for clues.
Troubleshooting
No MemoryDiagnostics-Results events appear
The test may not have completed. Run it again and let it finish without interrupting. Also make sure you are filtering the System log, not Application.
The test is stuck at a percentage
Some passes take a long time. Wait at least an hour. If it truly freezes, that can itself indicate a hardware problem.
Frequently Asked Questions
How long does Windows Memory Diagnostic take?
Usually 15 to 60 minutes for the standard test, and longer for the extended test or large amounts of RAM.
Does Windows show results automatically?
Sometimes a notification appears after sign-in, but it is easy to miss. Event Viewer always keeps the result.
Is Windows Memory Diagnostic reliable?
It catches many common RAM faults. For intermittent issues, a longer test with a dedicated tool is more thorough.
Summary
- Run mdsched.exe and let the test finish.
- Open Event Viewer > Windows Logs > System.
- Filter by MemoryDiagnostics-Results.
- Event ID 1201 means no errors; 1202 means hardware errors were found.
Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.
He specializes in writing content about iPhones, Android devices, Microsoft Office, and many other popular applications and devices.