Hello, I have an issue after I ran composer update (wanted to add a debug bar). something went wrong and I reverted back to a previous git commit. That did not change anything. I removed the vendor folder and tried again, same problem. Then I saw an update for October CMS and ran that. It fixed it! When I tried to install the debug bar again I got the same error. Now I'm stuck because there is no October update so my previous fix is unavailable. This error only appears in fronted, backend is fine. Does anyone know how I can fix this? Is there a way to re-install of check the october codebase? Because the update did something to fix it...

Your problem/answer is probably similar to this: http://octobercms.com/forum/post/last-update-broke-installation

Still nothing. /Users/herman/Sites/aquacell-waterontharder/vendor/october/rain/src/Filesystem/Filesystem.php is there and the same as https://github.com/octoberrain/filesystem/blob/master/Filesystem.php I tried setting all files and folders to chmod 777 and to user/group that other files had (my own username). Deleted all vendor folders and tried composer update (also with sudo). No changes, still same error. Everything was working fine for weeks and since a few days I get this. If anyone has other ideas, I would really appreciate it.

Have you tried forcing a reload of the current version through the backend update page? I had a similar problem with composer update (I have avoided it since) and forcing an update fixed it.

Thanks, never really noticed that option. Had to Google it to know where it was :-P https://github.com/octobercms/october/issues/2 But today there was update 181 and now it's working again. Will try force update for when it fails again. Not using composer is also not really a good option.