Wordpress error uploading PDF: ImagickException: Unable to read image blob; PHP message: Upload failed: String binary is zero after processing image

Symptoms

• WordPress instance is having issues uploading PDF files:

  PLESK_ERROR: AH01071: Got error 'PHP message: ImagickException: Unable to read image blob; PHP message: Upload failed: String binary is zero after processing image'

• Plesk is using Debian/Ubuntu

Cause

The ghostscript package is missing.

Resolution

1. Connect to the Plesk server via SSH.

2. Execute command:

   # apt-get install ghostscript