Reading a few from https://www.google.com/search?q=Cannot+pin+to+taskbar+in+windows+10+after+latest+update I don't see one fix.
If this happened to me I'd logout and reboot. If it still failed I'd run CHKDSK /F/R/X (link to follow) before I followed up with other ideas.
Read how at https://www.tekrevue.com/tip/fix-hard-drives-chkdsk-windows-10/
Hello, A few days ago I ran the latest Windows 10 update on a delayed basis (I chose a specific time of 8:00pm). It took close to 2 hours. When it was completed it restarted and my entire desktop had changed ie: background pic etc. and all my app icons from my taskbar were gone and now I can't "pin" any app to it. For example, if I want to run "Word" or "Google" browser, I must go there from my start button and execute it from there. This is totally "weird" to say the least. Obviously, any help would be appreciated.
It's got to be some problem with the registry and it could have happened during the update as our ISP was having problems during this time..
Thanks! for whatever you can offer.

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