Yesterday, while writing a blog post, I encountered an image upload error. The file would upload to 100% but then display “Upload Failed” with the message “Missing temporary folder.” I had recently switched VPS, so I initially suspected a directory permission issue for the images. It turned out to be a PHP configuration problem instead.
How to Fix:
vim php.ini
Locate upload_tmp_dir and change it to the following:
upload_tmp_dir = /tmp
Save and exit, then restart PHP. That’s it.
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