I am trying to flatten the file structure we have on SharePoint. Is there an OOTB but non manual way to move the contents of a folder up a level? I'd rather not download the contents of the folder, and then upload it all at again to a higher level. For some reason I cannot open the SP library in Explorer and adding to Trusted Sites doesn't fix that.
If Open in Explorer does not work, try to use Content and Structure in Site settings
You could also change the view to Show all items without folders. That won't technically move them out of one folder to its parent, but the effect might still be what you are looking for.
I've also used this concept paired with Column default value settings to make a view for each folder.
Regarding your issue with ExplorerView. Ensure you are using IE. I have several users that "accidently" get Chrome set as default browser, then Open in Explorer doesn't work.
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