For the record, of the several solutions I tried, the one that worked, stuck and fixed it is what is described here. I, too, would've preferred not to have made an "everyone" group but at this point, it's a pretty simple fix. Also, I'd add: make sure all the old groups have all permissions, just to be thorough. And uncheck the "read only" attribute AFTER creating this new group and apply, just to double down.
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http://answers.microsoft.com/en-us/windows/forum/windows_10-files/document-folders-marked-read-only-after-upgrade-to/4f00d3fe-82b0-4e6d-a92a-f81751aa6f51?auth=1
I've had the same kind of issue concerning a few random files in Win7. I didn't have any acces at all, and the workaround back then was hard to find, but simple to apply.
When you right-click the "main-folder" that you only have "read"-rights on, and enter properties, there is a security-tab, where there should be listed a few whitelisted-accessors. Those can be, but are not limited to; Users, System, Administator, etc...
Now, there should be a button just below the list, named "Edit" or "Manage" (translating this from a Danish operating-system...), and if you press that, you're given the option of adding or removing "accessors" and rights/allowances to them. Go ahead and press the "Add" button. Now, a new window will open with 3 slots - 2 of which should already be filled.
The last box should be empty, and here you should now write "EVERYONE" or "ALL" (again, translation from Danish...). Capital letters, may or may not be important. For me, it capitalised everything automatically.
Press the OK button, and select the "accessor" you've just created. Below the list, there should be 2 collums of squares with/without checkmarks. In the "Allow" collum, you should check all boxes, and in the "Deny" collum, all boxes should be un-checked. Duh.. ![]()
I have a PC, and have been using Windows-7 until today, when I started using the free Windows-10 instead.
One huge problem is that Windows-10 changed all my documents to "Read-Only."
(Regarding my documents, I use "Microsoft Office Word 2007," which has been working great, and I use it daily!) What can I do to fix this situation?

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