I can confirm the 'Ancestry' access suggestion - working well.
Just changed my address and then the graphical representation on one of my boards (with lots of custom text) this way:
I took the code from a page with no custum content by copying it, and pasted it below my custom text on the other site, replacing that code-snippet (be careful to select the exact same part/lines).
Alternatively you'll get that code by clicking on 'Insert Email' below the 'Add your Email' heading on the editing page. If you follow that way, it's a good idea to select the old code including "<!-- Begin encrypted email image" and "End encrypted email image -->" before you click on insert. Alternatively set the cursor at the end of any existing text/code, insert the address and then copy that code or just the short src= part into the existing code, replacing the old one. A bit tricky, have a coffee before you start ;-)
Aaaaaargh! Tried another board, and there I got that error too, working from the ancestry side ... Tried resetting to default, this time this worked - even from the Rootsweb side. Makes me wonder: How are we supposed to update our custom Info-pages? I've put considerable time and effort into a few of them ... (maybe I'll try later again).