I actually experienced this problem much in the way mentioned a few posts up on this page:
https://www.ads-software.com/support/3/18044#post-107440
That is, I changed the “home” URI in the first options tab and could no longer log in (even with all the suggestions mentioned).
Unfortunately, I’m not as savvy with mysql as the above poster was… so I didn’t know how to reset the option_id 105 field to my old “home” URI… luckily, I had no serious content and could drop all tables and reinstall.
It would be great if the poster above could detail exactly what needs to be done to change the “home” URI from the mysql command line.