Thank you for your very speedy reply.

In this particular case I am scanning the windows external hard drive as a practice run because a friend of mine has a similar seriously affected drive which he will be passing on to me to have a look at later. I’m not actually expecting to find viruses or errors on my own drive.

In the past I’ve used ClamAV for this kind of thing but was curious to try Avast as I have heard good things about it.

The drive appears to be mounted properly, normal disk related linux commands seem to operate well and the GUI file browser seems to operate well.

BTW I noticed a request from the moderator to search for problem solutions before posting. I always do this and rarely find the need to post, but in this case haven’t found anything relating to this error - apologies if I’ve missed it somewhere.

Thanks again for your interest and support.

Bernie M