Backup Manager in Plesk Control panel->Tools and Settings->Backup manager shows the error:
Error: Unknown file type
In pmmcli.log (C:\Program Files (x86)\Parallels\Plesk\PMM\logs) you may see something like that:
ERROR Validate failed: ActionProcessor <pmmcli.GetTasksListAction object at 0x022D38F0>
<response>
<errcode>1</errcode>
<errmsg>Invalid input parameters in '--get-tasks-list' command:
Task type must be 'Backup', 'Restore', 'Migration', 'Deploy' or 'ConflictResolve'</errmsg>
To fix this do following steps:
Copy directory above from other Plesk 11.5 server if it is possible or extract broken files from plesk.msi:
Extract plesk.msi archive to temporary folder:
C:\ParallelsInstaller\parallels\PANEL-WIN_11.5.30\dist-msi-Microsoft-2003-i386>msiexec /a plesk.msi /qb TARGETDIR=C:\tmp
Create backup of pmmcli directory: C:\Program Files (x86)\Parallels\Plesk\admin\share\pmmcli
Copy content C:\tmp\Program Files (x86)\Parallels\Plesk\admin\share\pmmcli to C:\Program Files (x86)\Parallels\Plesk\admin\share\pmmcli
Reinstall microupdates as below:
ai.exe --select-product-id panel --select-release-current --reinstall-patch --install-component base