Thread:Project:Support desk/Exception from line 1871 of /w/includes/filerepo/file/LocalFile.php: Could not acquire lock for 'npose n.png.'/reply

MediaWiki tries to acquire an exclusive (or shared) lock to a file, which means, that MediaWiki wants to prevent any access to a given file, until the actions of MW are finished. Read more about file locking.

To fix this problem, we must find out, what the problem is :) Is your webserver allowed to read/write the directory, where your images will be saved?