Actually this doesn't work for most adhesives (except by friction).
-----You'd be surprised; have you ever tried? ...And of course you've got to rub a little.
* I got rid of the most persistent and sticky glues with isopropyl alcohol (99% solution).
Use a cotton piece of cloth, and put some on it, then rub; if the surface is glass or metal, it'll come out no sweat.
...Only with plastic materials (surfaces) that you have to be careful.
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Mark, just rub a little more that's all (apply more pressure). ...I know exactly your situation as I had the same in the past, and I fixed it the way I described it previously. It goddamn works or I wouldn't be posting it in the first place! :b