Currently when an error/exception occurs, Piwik returns a 200 HTTP status and that can mess up with a lot of things.

Current status:

Target:

For uncaught exceptions, we are not sure we want to return a 500 because exceptions could be for example "unknown idSite" which should be a 404. Same for 403 I guess (I haven't looked at the code)

However it definitely should not be a 200 as it is now. We should probably improve how exceptions are handled in some cases (404, 403…).