Solution mentioned by hexagon12 are the generic steps to deal with any windows store error. While these don't guarantee the fix but helps most of the time...

In addition, Try and use the Inbuilt...

Thats Right, BTW are you getting any error while activation?

IF you have problems then clean install windows 7, Make sure its fully activated, Upgrade to windows 10 Using Media Creation tool.
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There is nothing on the web about this error code. Did you managed to fix it? please update here if yes.

Make sure your time zone is Correct.

Goto Start > Settings > Privacy > Turn Off everything. Try if this helps.

Its a universal issue, Refer to this > Service Alert: Windows Store crashing on Windows 10 PCs and Mobile phone | Windows Central

Make sure you have enough space in C drive for windows 10 and windows 7 old folder... this might be the case..

also Increase the size of system reserve partition with the help of easeus software...

Cool, easy was to click on notification icon in task bar. just in case if you need to know for in future... good thing is you have already figured it out anyways.

Found Solution? If not then Check this > Fix The Server Stumbled with Error 0x801901F7 in Windows 10 | Fix Errors

there are 3 methods explained, Update back with which one worked if possible.

I don't know if this will help but seems like it is pretty common error as once even i got this error in my Windows... This Guide Helped me > Error Code 0x80070057 - Causes and Methods to fix it |...