mediawiki sistemli siteme jpg yükleyemiyorum!!

siteme resim eklemek istediğimde aşağıdaki uyarı çıkıyor. sorunu bilen varsa lütfen yardımcı olsun..
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couldn't rename /tmp/phpoHrRf7 to have a better extension at /tmp/phpoHrRf7.jpg
Backtrace:
#0 /var/www/vhosts/___mydomain___.com/httpdocs/includes/upload/UploadBase.php(634): UploadStash->stashFile('/tmp/phpoHrRf7', Array, NULL)
#1 /var/www/vhosts/___mydomain___.com/httpdocs/includes/upload/UploadBase.php(646): UploadBase->stashSessionFile(NULL)
#2 /var/www/vhosts/___mydomain___.com/httpdocs/includes/specials/SpecialUpload.php(367): UploadBase->stashSession()
#3 /var/www/vhosts/___mydomain___.com/httpdocs/includes/specials/SpecialUpload.php(461): SpecialUpload->showUploadWarning(Array)
#4 /var/www/vhosts/___mydomain___.com/httpdocs/includes/specials/SpecialUpload.php(192): SpecialUpload->processUpload()
#5 /var/www/vhosts/___mydomain___.com/httpdocs/includes/SpecialPage.php(578): SpecialUpload->execute(NULL)
#6 /var/www/vhosts/___mydomain___.com/httpdocs/includes/Wiki.php(251): SpecialPage::executePath(Object(Title))
#7 /var/www/vhosts/___mydomain___.com/httpdocs/includes/Wiki.php(63): MediaWiki->handleSpecialCases(Object(Title), Object(OutputPage), Object(WebRequest))
#8 /var/www/vhosts/___mydomain___.com/httpdocs/index.php(114): MediaWiki->performRequestForTitle(Object(Title), NULL, Object(OutputPage), Object(User), Object(WebRequest))
#9 {main}