What is a WER file?
A .WER file is a system log generated by the Microsoft Windows operating system. When a software application crashes, hangs, or experiences a critical fault, the Windows Error Reporting service creates this file to document the event. These diagnostic logs help system administrators and developers understand exactly why a program stopped working.
How to open WER files?
Because most .WER files use standard text formatting, you can read them with basic text editors like Notepad or Notepad++. Advanced engineers often analyze these files alongside .DMP memory dumps using WinDbg or other Microsoft diagnostic tools to find the root cause of a software crash.
Best practices and troubleshooting
If you find many .WER files consuming your hard drive space, you can safely remove them. The best practice is to use the built-in Windows Disk Cleanup tool to delete old error reports safely. While you can disable the Windows Error Reporting service to prevent new .WER files from forming, keeping it active provides important data for troubleshooting recurring system crashes.
Summary
If you need to quickly read a crash log, viewer.online/wer analyzes .WER files to identify their exact format and creator software, shows which programs can open the file, and usually previews it. Because .WER files use the known UTF-16 (LE) format, viewer.online/wer can safely open and display them online, eliminating compatibility problems.