Step 1: Log in to Plesk Panel
Step 2: Go to Websites & Domains and click on ‘Hosting Settings’
Step 3: Inside, ‘Web scripting and statistics’ tick on ‘Custom Error Document’
Step 4: Go to ‘Websites & Domains’. Under ‘Virtual Directories’ click on ‘Error Documents’
Step 5: Click on the error we want to set up for our page.
Step 6: Select file or URL and our page for the same error and click on the button.