Query Summary Fields

@Lee Grisham I don't know if I ran into the exact same thing as you are encountering but I got a similar error. The case is still outstanding, but there are a couple of things that I came across that may be helpful in the interim. The most straight-forward way around the issue was running the query in database view rather then web view (if you have that option). It sounds like you isolated the issue to using summary fields but, just in case it helps, one thing I found in my situation (which didn't involve summary fields) through trial and error was that the query that threw the error was using the "Select from" option to read from another query. That other query had a few lines of "One of" criteria: "Phone Number one of…. OR Phone Number one of… OR Phone Number one of…". What I found was that reducing the total number of phone numbers (emails in this case) that the query was checking would allow things to run as expected in web view. Hopefully this helps or at least helps you figure out a workaround.

when you say "Seems to only work on query when I have summary fields used" do you mean query works when you have summary field, or error comes up when you use summary fields?

I don't remember I seen you posting in Developer forum if you did play with API, then i would suggest running the query via API and see if you still see a problem