Disabling anti-virus on access scan of all FOLDERS with *.gdb resolved the issue for us
Running 10.5.0.6491 on windows 10, saving to a network drive and I get this error. If I close down and re-open the same project there are no issues for while. any more recent solutions?
SOLUTION:
In my case I was using arc pro, on a server network. Would used a FC to FC. Would then become read -only. I would right click on my new feature class>Properties>Metadata
The first box is a drop down, I chose "Layer has its own metadata"
Sounds like a possible issue with Pro's new 2.1 functionality to have metadata for a layer and feature class separately. Please consider reporting this issue to support so they can get it fixed.
I also had encountered this problem. Didn't realise that my compressing the geodatabase made it read-only... a problem of my own making... 😞
Ah, Compact (usually a good idea) vs Compress (need to consider your use case).