WhyCrashed

.wer · text/plain

What is a .wer file?

Windows Error Report

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About the format

A .wer file is the report Windows Error Reporting writes every time a program crashes or hangs. Despite the obscure extension it is plain text (UTF-16), a list of Key=Value lines: the event type (APPCRASH, AppHangB1), the application name, version and path, and the crash signature — including the faulting module (the DLL or EXE that actually took the program down), the exception code, and the offset inside that module. Reports live under C:\ProgramData\Microsoft\Windows\WER in ReportArchive (already sent or expired) and ReportQueue (waiting to send), one folder per event, each holding a Report.wer and sometimes an accompanying minidump. When a program keeps dying silently, its ReportArchive folder is often the only witness: the faulting-module line frequently points straight at a bad plugin, overlay or driver DLL rather than the program itself.

How to open a .wer file

Windows

  • WhyCrashed App-Crash Reader (browser)
  • Notepad (readable but raw)
  • Reliability Monitor (summary view)

macOS

  • WhyCrashed App-Crash Reader (browser)
  • any text editor

Linux

  • WhyCrashed App-Crash Reader (browser)
  • any text editor

Is a .wer file dangerous?

No — it's a text report. It reveals which programs you run and their versions, which matters only for privacy.

Related file types

.dmp.mdmp.evtx

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