How do I make jpeg image background transparent?

[metoo]

This thread is as relevant today as when it was first launched. I've just done a screen dump to illustrate the problems I'm getting and am unable to resolve as PS is not my forte and I need to convert a logo with a white background so that I can import the converted image into AID. When I followed what appeared to be the simplest procedure of all the suggested methods, I was unable to pass first base.

I want to remove the white background completely leaving just the the image and text without any white background whatsoever. From what I've seen on this thread, the best way for me to do this would appear to be the background eraser tool which gave me a CS5 error message: Could not use the background eraser because the target channels do not cover the composite".

What are the "target channels" and "composite" and how do I make the former cover the latter so that I can move to the next stage.



Thanks for all your help in anticipation.

Kind regards