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What I see is:
1. if when I install ubuntu I choose the partition to have the mount point /home then the  blockchain will be downloaded to  the larger partition



2. if I use the partition like a  normal partition/external device (lets say an external hdd) will not work



I give all the directories  to have 777
I also choose the mount to be "media" but same error, unfortunately I can't give the mount point /home I think that can be done only when I install ubuntu


I wish to have the blockchain to the partition like in case 2 but I really do not know why


Other think very odd, when I start the bitcoin QT  and I choose the directory in the window "Choose data directory" the "make a new directory  button is grey , inactive, and the folders are not showing there



at this point I try it on 3 different computers
I'm new in ubuntu  but I watch some online curses about linux command line   ubuntu OS  and I'm good on computers but  I really do not get it why the blockchain can't be save where I wanna.

I can easy install windows 10 and  put bitcoin there but I wanna have ubuntu (give me a reason to learn about linux system)


best regards and happy Christmas to all from here