Can't open documents

I have windows10 installed but some virus infected my firefox browser and i had no option but to refresh my pc which i didn't know would install windows again ,previously when i upgraded to windows 10 from windows7 .. i could see windows.old folder in which i had all my 7's programs but after this refresh ,there was windows.old file of only windows 10.So i assume my 7's all gone.Anyway, after refreshing , i click on start and it didn't open any thing.Tried several fixes which include some kinda script in power shell but it didn't worked.Then somewhere i read ,try to create a new account.I created a new account and login in it but start menu was not working even in that.I deleted the old account and then tried to login with this new account but it didn't worked. I lost all my documents related with old account.Then i decided to restore my pc to get back my documents ,eventually i found recently created restore point by windows,i ran it and was able to get back to my deleted account and my documents,everything was there documents,pics,programs .However i can't open any documents.When i try it says,"Access is denied".
I have already took the ownership and give full control to a file which i want to open but its not working.Tried to enable built-in administrator account and login with that account and opened that file but same result.Documents folder has "Read-Only attributes checked and when i uncheck it ,it apply the attributes to a single folder under documents not to all folders and files.Some files under documents are encrypted and some are read-only,I also copied documents folder to another drive D when i was running windows7 but it shows the same error "Access denied"when opening files from D drive,Is this related to my previous account which i have deleted and restored back?When i I asked on Microsoft they said, they are working on this and would reply,don't know they will reply about start menu or documents,I don't want to reinstall windows ,is there any solution to this?
Thank you

run an anti program first to see what and if you do have a bug. Malwarebytes is good. Do you have up to date AV? Not teaching you to suck eggs but you never know? 7 should be in windows.old if 10 allows it. I dont know that due to not yet being on 10.