Coonection should of course be connection.
Also the line should read : I have been using it for pretty much a month without issue.
My "Excel as a database" experience is limited so...First, is there a table or sheet that is named "combined"? Second, read this thread. It may not answer your specific question but shows that there are issues with the JET driver and that, ultimately, could be your real issue.
I would highly recommend using a real database. Excel is not a database application and should not be treated as one! At the very least get someone to develop a process to put the data into a proper SQL db or Access (it's better than nothing).