Adding Subscription in plesk, with mail service. Gives following error.

Error: A specified logon session does not exist. It may already have been terminated. (Exception from HRESULT: 0x80070520)
In Microsoft.Web.Administration module Exception type: System.Runtime.InteropServices.COMException
at Microsoft.Web.Administration.Interop.IAppHostMethodInstance.Execute()
at Microsoft.Web.Administration.Binding.AddSslCertificate(Byte[] certificateHash, String certificateStoreName)
at Microsoft.Web.Administration.BindingManager.Save()
at Microsoft.Web.Administration.ServerManager.CommitChanges()
at ServerManagerFactory.commit()
at IISServerManager.commit(IISServerManager* )
at Commit common changes(WebServerManager::updateWebMailLinks line 2713)
at updateWebMailLinks()(WebServerManager::updateWebMailLinks line 2716)
at execute console command –update-webmail-links(vconsoleapp::start line 122)
at execute “C:\Program Files (x86)\Parallels\Plesk\admin\bin64\websrvmng.exe” –update-webmail-links “–config=tmpB2DD.tmp”(vconsoleapp::run line 139)
(Error code 1)

Reason : There is a manually added binding in IIS for MailEnable Webmail for 443 port. SSL certificate is not selected:

Resolution

  1. Connect to the server via RDP.
  2. Go to IIS Manager > Server_name > Sites > MailEnable WebMail / webmail(Horde) > Bindings.
  3. Check all records related to Port 443 via webmail.domain.com > Edit.
  4. Next thing you can try is switch the mail server to horde.
  5. Please refer https://www.24x7serversupport.com/blog/index.php/how-to-change-webmail-type-for-all-domains-in-plesk-windows/
  6. Then login to plesk >> tools and settings >> webmail >> disable mailenable
  7. Try adding domain again.

Step 2

Login to plesk

Subscription >> Add subscription >> Add details like domain, username and password.

In service plan >> select NONE >> make sure you uncheck “Proceed to customizing the subscription parameters after it is created. Note that this will make the subscription locked for syncing.”

Dont select any other option. Click on Ok.