Windows 10: Where did my system restore go?

Somehow my system has changed not by my doing. Now I can't open Excel files or Word files. What happened? I tried to use a "restore point" I had created days, or weeks ago and I can't even pull that up. I have a good virus program, PC Matic, Has microsoft done something?

:)

 

System Restore Error 0x81000203

Good day,

We can see here that you are having issues performing system restore on your computer. Having said that, we need to determine the cause of this problem. Before we proceed, may we know the following:

• Any changes made on the computer prior to this concern?
• What troubleshooting steps have you tried so far?
• Are you getting any error messages when trying to perform system restore? If so, can you send us a screenshot?
  Note: Please do not include any personal information.
• Have you performed all the suggested troubleshooting steps found on this thread?

 

Missing icons / buttons after System Restore

Hi Terrie,

To address your concern, we suggest that you try to undo the restore or pick another restore point.

Please follow these steps to access system restore:

• Right-click (or press and hold) the Start button, and then select Control Panel.
  
• Search Control Panel for Recovery.
  
• Select Recovery > Open System Restore > Next.
  

Let us know how it goes.

 

How to delete inactive System Image Restore Points in System Restore

Windows 10 64-bit.
When I click "show more restore points" in System Restore I see a bunch of old "system image restore points" that were deleted in past and do not correspond to any currently active restore points. Clicking any of these old restore points, I simply get an error message saying they could not be found, and to select another restore point instead.I would like to delete these restore points listings but have been unable to do so.
So far, I have tried steps mentioned below without any luck :

Disk Cleanup through (C Properties
Disable System Protection (OFF and ON) in System Protection for OS (C
Disk Space Usage to minimum (slider button all the way to the left then 'Delete all restore points for this drive'),
Delete all shown Restore points in CCleaner (the problem ones do not show here),
Reset Windows Backup to Default in Windows 10 with 'Reset_Windows_Backup.bat' utility.

Any suggestions highly welcome.