[Tim Harris]

Hi, I have omnifocus installed on two desktops and one iphone. Webdav syncing on one desktop just stopped working. I get the response "server returned “unauthorized” (401) in response to a request to “PROPFIND /OmniFocus.ofocus”. No problems on the other desktop or iphone. If i reset the preferences on the webdav screen on the application, and re enter the location, I get the same response and I don't get the option to supply the username and password.

[Brian]

There are probably multiple keychain entries for the server you're connecting to on that machine, and one that doesn't actually work is being used.

Open the Utilities folder, launch Keychain Access, and use the search box in the upper right to search for the server; delete any bad keychain entries and re-launch OmniFocus. It should start syncing again.