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Diagnostic Mode

Chromium (and Google Chrome) comes with a set of built-in diagnostic tests that any user can run. These tests can help determine the root cause of the following problems.

Work in Progress : Diagnostic mode is currently only available in the tip-of-tree version of Chromium for Windows and in the developer channel version of Google Chrome for Windows. Furthermore, only a small set of diagnostic tests currently run (more are planned in the future).

Diagnostic mode is an environment that runs a set of tests before the browser starts. These tests vary in sophistication, from trivial checks that critical files exist, to more complex (and time consuming) tests that test the integrity of the key databases. Each test can pass, fail or simply be skipped if the test is not applicable. The output should be used as as a starting point for further, more specific, investigation and troubleshooting.


Diagnostic mode does not automatically send any information to Google. It is up to the user to copy the text output from running diagnostic mode that they consider appropriate and helpful for others to see. Furthermore, care has been taken to expose little to no personal information in the diagnostic output so that users can feel comfortable sharing it with internet help groups.

How to run (windows only)

  1. Make sure no instances of chrome.exe are running. Check in the Windows Task Manager for any zombie chrome.exe processes and end them if necessary.
  2. Open a command line session (cmd.exe)
  3. Change directory (cd) to the directory of chrome.exe, for example,in Vista, regular chrome install is in C:\Users\<user name>\AppData\Local\Google\Chrome\Application
  4. Type chrome.exe --diagnostics [enter]

A second console window will open and the tests will run automatically, and you should see something like this:


This shows a run where all tests passed. If a test fails it will be marked with a [FAIL] entry.