If you are running Apache with mod_security, try to disable mod_security to confirm that one of its rule is not good and triggering a false positive.
Windows is finicky and does not provide a meaningful error message on failure, do try WebDrive or NetDrive (http://docs.filerun.com/webdav).
The PHP configuration looks fine and there isn't much there that can affect WebDAV.
The logged PHP error is not from FileRun.
You'll have to contact us for that: https://filerun.com/contact
No, sorry. You can continue using the current app you mentioned for that purpose.
The Pixlr public service has also been discontinued. FileRun's own image editor will be included with the next update.
You should actually try a WebDAV client, to connect, browse folders, download files, not just trying the WebDAV URL in a browser, because I have a feeling it will not work for you. You should check your HTTP access and error log, as it is possible that your HTTP server is rejecting PROPFIND requests.
The HTTP logs will not help much. Look in FileRun's user activity log (inside FileRun's control panel). Other logs that might help would be the PHP error_log (if this is a PHP related problem).
This forum uses the FileRun client account login, rather than its own, so you can change your password here: https://filerun.com/client-area/change-pass
The connection URL should be the simple URL of your FileRun installation (same URL you use in the browser), not with "/dav.php" or anything else after the folder URL. Could that be it?
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