PleskFatalException error

The Plesk error will look like this
ERROR: PleskFatalException DefPackageMng() constructor failed: defpackagemng failed: Access is denied. (Error code 5) at CreateProcess 'C:\WINDOWS\system32\cmd.exe /c ""C:\Program Files\SWsoft\Plesk\admin\bin\defpackagemn
g.exe" --get"' at execUtil C:\Program Files\SWsoft\Plesk\admin\bin\defpackagemng.exe --get on c:\windows\system3
2\inetsrv(PleskSrvClient::execUtil line 435)
at execute console command --get(vconsoleapp::start line 128)

The solution is to grant full "System" access to C:\WINDOWS\system32\cmd.exe.

Windows Plesk webmail shows 404 error

Check whether the domain contains webmail virtual directory with " A directory located on this computer" as "C:\Inetpub\vhosts\webmail\horde"

If it is existing do the following to fix the issue.

cd %plesk_bin%
websrvmng.exe --reconfigure-webmail
defpackagemng.exe --fix --type=webmail


This will fix te issue.