when you say original filesystem do you mean the drive omv is install on? if so you need an addon to use this as its not recomemded.
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Solutions to common problems
IF YOU GET AN ERROR, PLEASE COPY THE ERROR FROM THE BELL IN THE TOP RIGHT PART OF THE OMV WEB INTERFACE AND PASTE IN YOUR POST!
Here is a list of problems with potential solutions (these videos may help as well):
Problem #1: Web interface has missing fields and/or items showing that have been uninstalled and/or something just isn't working right.
Solution #1: Clear your browser cache or try ctrl-shift-R.
Problem #2: I mounted the drive using the command line or GUI tool and I can't pick that…
Here is a list of problems with potential solutions (these videos may help as well):
Problem #1: Web interface has missing fields and/or items showing that have been uninstalled and/or something just isn't working right.
Solution #1: Clear your browser cache or try ctrl-shift-R.
Problem #2: I mounted the drive using the command line or GUI tool and I can't pick that…