Thread:Project:Support desk/Stuck in a 'Read only" mode following Upgrade (1.16.4 - 1.17.0)/reply (2)

If you had really messed up re-write rules/wrong $wgScriptPath settings, that could potentially cause this. More likely a result of moving from windows to unbuntu (some webserver config not moved over or something like that) then a result of upgrading mediawiki.