Try placing the images in the same folder as the source file (the .txt file).
Then you should just be able to use the exact name of the image (no path required).
I wrote this up in a blog post many years ago (but it hasn't changed):
I went back to my source files for this example, and it still works in InDesign CS6.
We don't know what you mean by "it didn't work" unless you tell us what happened when you tried. What Steve has said should work, but I notice in the paths that you included in your post that there is probably at least one delimeter missing unless your file itself is named "imagesqrcode_AberdeenENG.png"
Agree with Steve and Peter – put the images AND the .txt file into a folder – the merge should work from there. The other bonus of doing this is that only the filenames are required, not the complete path to the link.
placing it in the file works like a charm but because i will sometime have over 15 .txt files i wanted to avoid doing that but i will take that solution it works well . if i do it the other way its merging every other time which is weird. this works and it is perfect thank you for your help.
One possible problem might be the merge preview, which is buggy. It's best to take a leap of faith and just run the merge without a preview, then check to be sure it's correct. Since most merges take only a few minutes, this isn't too onerous most of the time.