I've tried the DIF product removal on a border, which came off in layers, however, I am left with a gummy residue that I cannot seem to remove. I have scored the wall, used the DIF, scraped and washed all to no avail. Any suggestions?
The glue on borders can be hard to remove because of of the amount they put on them. I would use the DIF gel to remove what you have left as it will cling and not run off and should make it possible to remove this glue.