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On my network is an Ubuntu computer mapped as letter "U", besides other things I use it to backup my wife's and my computers. I was doing some cleanup, deleting some files I no longer needed and all of sudden I get this error:



I can still access the Ubuntu computer over the network, but Windows Explorer can't access the U drive, but it can see other computers on the network.

My Windows version is 1903, and Ubuntu is 18.04

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After a reboot WE was able to access the U drive.