Restored to stock. Tried root browser and esfile Explorer. Yes I'm rooted. Twrp recovery newest. Stock kernal
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Try using root explorer or es file manager, granting super user permissions (in es you'll see it on the left tab under the heading "root permissions" with an on/off button) and navigating to your internal. Try moving a file around, or creating a folder. See if you are prompted to mount your internal memory.
If your internal memory is write protected for some reason, you should be able to copy a file to your external storage or computer, but any write operations, including downloading pics from the Internet, downloads from the Play Store, all would fail).
Now try it with the built in file browser that came with the stock rom.
Report back.
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