I have a solution for this error and I thought I would share it here.

When you input the tag for your gallery folder, ie: {gallery}summer_trip_to_italy{/gallery}, do NOT copy and paste from the documentation page. When you paste it into Joomla's article interface with TinyMCE, the bold tags are retained. You must type it in yourself, or go into the html editor and remove all of the extraneous tags.

Once I figured that out, everything has worked perfectly.

ginowhitaker,

Thanks for posting this. html markup from copy & pasting the gallery name into the tag was causing me to pull my hair out till I read your post & looked at it in html mode.

Thanks!