Whenever I select My Forum and the select posts since last visit, several times I have noticed threads from forums that are not listed in my settings. Does anyone know why this is happening?

you may have broken out of myforums mode. if you select All Forums from the main drop down it takes you out of myforum mode or if you come into the forums from the homepage I believe you should be in all forum mode (not myforums). in those cases you will see posts from forums outside of your myforum selections.

I don't follow, from the home page I select my forums and then in the next window I select posts since last visit. Are you saying that by selecting posts since last visit that is what is taking me out of MyForums???

On the homepage are you selecting myforums from the forum drop down menu or just clicking the Forums link itself?

The My Forum link located on the left side of the screen.

try clicking the myforum coin atop the forum page then clicking new posts and see if results are correct.

It appears that it is working correctly, Thanks