Why does Windows 10 remove applications

[Guest MBKITMGR]

Over the years of supporting Win 10 one of its more annoying behaviors is when it decides to "blow away" an application that is installed on a device. I have seen this only once with Windows 8

 

I've seen many episodes (three times in the last 10 days) of it removing Office products, Office suites (2016 and O365), minor utils like Acrobat Reader, Small Bus financial packages and enterprise products, device software, device drivers....

 

Software is installed under admin privilege, or where it requires I promote the user to Admin of their Device install as them then demote to user. This is regardless of whether the machine is Domain Joined or Standalone. Even those less popular situations where the user has to be an admin to run a program has seen that program vaporized.

 

Then there is today. A very popular financial package (MYOB) that has been on this PC for 3 months, was in use yesterday when payroll processing began. Today the user has come in logged on and its gone - no evidence it was ever installed, no folder structure + no shortcuts + nothing in Apps & Features. Luckily it wasn't the on prem version where the data files live in the same folder as the application files :(

 

• Why does Win 10 do this?
  
• When it does how does it determine the application must go?
  
• Are there events recorded in the event log that I can look for that tell me this has occurred and why?
  
• On the subject of event log entries, are there ones I can monitor and be notified that an app has been removed, so that I may jump in and address before the customer comes in and wants to start their day in a normal way?
  

 

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