Trevor keys

I have been given fax numbers from countries throughout the world.
when i reply to these fax numbers my fax doesn't get through.
what extra numbers (letters) do i need to add.?
 

Hello and welcome to Tom's Hardware Forums.

You need the international dialling code list so if you're sending to the States, start off with 01 then drop any zero that might be on the original number. For the UK it's 44, Holland 31 and so on. This site shows all of them, I hope. http://www.countrycallingcodes.com/