How to open a .dmp file
Memory dump · Diagnostic
A .dmp file is a snapshot of memory written when Windows or a program crashed. It is not readable in a text editor. You analyse it with WinDbg, and the useful part is usually one line naming the driver that failed.
What a .dmp file actually is
When Windows hits a stop error, it writes what was in memory to C:\Windows\MEMORY.DMP and smaller minidumps to C:\Windows\Minidump. Applications write their own dumps when they crash.
The file is a binary image of process or kernel memory. Opening it in Notepad shows noise, because there is no text in there to read; it needs a debugger that understands the structure and can match it against symbol files.
Why it will not open
Nothing on a normal Windows install opens a .dmp. The debugger is a separate download, and without symbol files it produces output that names addresses rather than drivers, which is why so many people give up at this step.
Step by step
Windows
- 01Install WinDbg from the Microsoft Store, which is the current and free version.
- 02Open the .dmp with File, Open dump file. Minidumps live in C:\Windows\Minidump and are the small ones you usually want.
- 03In the command box run: !analyze -v
- 04Wait. The first run downloads symbols and can take several minutes.
- 05Read the MODULE_NAME and IMAGE_NAME lines. That is the answer: a driver file name such as nvlddmkm.sys points straight at the graphics driver.
- 06If you only want the summary without installing anything, BlueScreenView reads minidumps and highlights the likely culprit, though it is far less precise.
macOS
- 01Windows .dmp files are not analysable on macOS in any practical way; the debugger and symbols are Windows-specific.
- 02macOS writes its own crash reports instead, viewable in Console under Crash Reports.
What usually goes wrong
A driver name is a lead, not a verdict
The module named in the dump is where the crash surfaced, not always where it started. Faulty RAM and an overheating GPU both produce crashes that blame whatever driver happened to be running. Treat the name as the first clue.
Do not upload dumps to random analysis sites
A full memory dump can contain anything that was in RAM at the time, including passwords and open documents. Minidumps are far smaller and safer to share, but a MEMORY.DMP deserves care.
Programs that open .dmp
Our pick, in order. Every one links to the publisher's official download URL and the SHA-256 hash of the installer, so you can check the file before you run it.
Common questions
- How do I read a Windows .dmp crash file?
- Install WinDbg from the Microsoft Store, open the dump, and run !analyze -v. After it downloads symbols it names the module that failed, which is usually a driver file such as nvlddmkm.sys.
- Where does Windows save crash dumps?
- Full dumps go to C:\Windows\MEMORY.DMP and small ones to C:\Windows\Minidump. The minidumps are the ones to analyse first: they are a few hundred kilobytes and contain the crash context.
- Can I just delete .dmp files?
- Yes, once the problem is solved. A MEMORY.DMP can be several gigabytes, and Disk Cleanup lists them as system error memory dump files. Keep them while you are still diagnosing.