Back to my Mac

I'm afraid I still can't get Back To My Mac to work - I'm getting the attached message when I try and assign my BTMM application to my office computer. What am I doing wrong? The message infers that it's already set-up but I don't think it is

Hi

I feel I'm getting closer to at least identifying the problem. I have placed another Mac in my office, using the same wifi network and I can connect to this machine via BTMM, so I feel the problem lies with the host machine.

Are there any settings on this the iMac I may have wrong, bearing in mind i can access this machine via BTMM when I'm in the same locality, but not when I'm further away and connecting using a different network.

Any suggestions gratefully received.

I feel I am getting a little closer to identifying the problem with my BTMM. I set up another iMac in my office, using the same network as the 'problem' machine and could connect to this fine. So it seems the problem lies with the host machine . I can connect to it when I'm in the locality but not when I move further away and have to use a different network. So, there must be a setting on the host machine which is blocking connections from different networks?

Hi this makes sense thanks - but how do I know if my BTMM connection is being blocked and how do I change the firewall settings?

Thanks again

Hi - I am the office people - one-man band and (as you may have guessed by now) pretty clueless on this type of technical issue. Is there some kind of idiot's guide on how to do this?

Many thanks

Hi - I have got so far with changing my router settings but I now need to know what Port Range BTMM uses - can you help?

Many thanks

Hi -many thanks.

There are a number of ports listed as being used by BTMM. Would I take the first one (500) as the start of the range and the last one (49152– 65535) as the end of the range?

Hi

I am being asked for a range, so it looks as though I have two numbers to enter. Could you tell me which please?

Thanks once again