Well, ordinarily, it's not possible to
REMOVE files by using Task Manager, only ending tasks that are running in RAM memory or killing services that are also running in RAM memory. That's just terminology however, I understand what you were trying to do. Neemo's suggestion is certainly worth doing, as 80% of the broken computers that come to me have failed due to spyware virus infection and damage from using poor quality malware tools to remove the virus itself. This often results in an unstable or unbootable system and requires more advanced windows repairs such as in-place upgrade, reset, or windows reinstallation after drive wipe.
***CAUTION: Attempting any of the virus scan/removal methods or even running basic windows repair tools such as
CHKDSK or
SFC requires that you
FIRST BACKUP ALL OF YOUR PERSONAL DATA TO EXTERNAL MEDIA! THIS WOULD INCLUDE YOUR LIBRARY FOLDERS FOR DOCUMENTS, PHOTOS, MUSIC, VIDEOS, AND ANY SAVED E-MAILS OR ATTACHMENTS IN ORDER TO PREVENT IRRETRIEVABLE DATA LOSS!!!. Remember this; running any Windows repair tools from basic repairs such as Chkdsk or SFC or others to the more aggressive windows repairs up to and including full Windows reinstallation from factory Recovery Media have a good chance of borking your windows!

The more aggressive the software repair, the higher the risk of fouling up your machine.

Therefore, it's a best practice of licensed and professional computer technicians to do a backup of all customer data to external media as mentioned above
PRIOR to starting any repair attempts including fixing Certificate problems, which can be quite tricky to fix. Sometimes, it's a 10 minute fix as neemo suggested, other times it can take weeks or months to track down and repair.
Here's a link to help I wrote to help you with further troubleshooting if neemo's fix fails to fix your problem and you get to this point:
Windows 10 - Unclickable Task Bar.
Best of luck,
<<<BIGBEARJEDI>>>