read-only file system

[jegb]

after a while of leaving the node syncing with the wallet on the ext usb drive, this is what happened:
SolarCoin: Error initializing database environment /media/sda1/solarcoin! To recover, BACKUP THAT DIRECTORY, then remove everything from it except for wallet.dat.
terminate called after throwing an instance of 'boost::filesystem::filesystem_error'
what(): boost::filesystem::remove: Read-only file system: "/media/sda1/solarcoin/solarcoind.pid"

Then trying to take over ownership again of the drive via chown, this is what it resulted:
EXCEPTION: N5boost12interprocess22interprocess_exceptionE
Read-only file system
solarcoin in AppInit()

terminate called after throwing an instance of 'boost::interprocess::interprocess_exception'
what(): Read-only file system

any hint to make the usb drive read/write again?