A website hosted in Plesk is not accessible: open_basedir restriction in effect

Symptoms

• A website is not accessible with one of the following errors in a web browser:

  404 file not found

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  500 external Server Error

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  Error 500 move_uploaded_file(): open_basedir restriction in effect. File(/path/to/the/directory) is not within the allowed path(s): (/var/www/vhosts/example.com/:/tmp/)

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  No input file specified.

• The following error message appears in the domain's Logs page (Domains > example.com > Logs):

  <...> open_basedir restriction in effect. File(/path/to/the/directory) is not within the allowed path(s) <...>

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  Uncaught Exception: Session: Configured save path '/path/to/the/directory' is not a directory, doesn't exist or cannot be created.

Cause

The PHP script is trying to access the folder for which access is not allowed. This restriction is defined by the PHP open_basedir variable for each domain separately. By default, open_basedir allows access to the tmp and domain's document root directories, as well as the system's default sessions path.

Resolution