Domain or Plesk shows Error 500.19: Cannot add duplicate collection entry of type 'mimeMap' with unique key attribute 'fileExtension'

Plesk for Windows kb: technical ABT: Group B

Applicable to:

On accessing a Domain, Plesk Interface or Domains > example.com > IIS Settings the following error is shown:

Error 500.19: Cannot add duplicate collection entry of type 'mimeMap' with unique key attribute 'fileExtension' set to '.srt'
The following error appears when migrating a subscription:

Command execution failed on the source server 'source' (203.0.113.2) with non-zero exit code.
command: "C:\Program Files (x86)\Plesk\admin\bin64\websrvmng" --get-mime-types --vhost-name=example.com
exit code: 1
stdout: Filename: ?\C:\Windows\system32\inetsrv\config\applicationHost.config
Line number: 39996
Error: Cannot add duplicate collection entry of type 'mimeMap' with unique key attribute 'fileExtension' set to '.srt'
Website's static content like images, .css, .js files cannot be loaded

Two identical MIME types are specified.

Remove the MIME type specified in the error:

For a single domain via Plesk Interface

Connect to the server via RDP
Create a backup of the file C:\Windows\System32\inetsrv\config\applicationHost.config
Open file C:\Windows\System32\inetsrv\config\applicationHost.config with a text editor
Remove the text in line with number mentioned in the error message and save the changes

Server wide

If Plesk Interface is affected

Connect to the server via RDP
Open Internet Information Services (IIS) Manager > <SERVERNAME> > Sites > pleskcontolpanel > MIME Types
Remove one MIME type with extension ".srt"

Internal because the exact steps not are clear

For a single domain via web.config