Before I get started Apple Configurator Support is free for ALL school districts. 1-800-752-7753
Welcome to my he-ll, folks! I have 5,000 + iPads in my school district that I have to support sll of them pretty much by myself. I have ran the gamete of errors and I also have an Apple Engineer at my disposal. So, I feel that I have it a little better off then most.
1st make sure all of the software is updated. OS 10.8 +, newest iTunes, newest AC. (The newest AC fixes VPP code bugs.)
2nd Make sure that you are using the correct Apple ID. I know it sounds elementary, but I have 100 school sites and all of them have their own Apple ID, so does each department, such as After School, ELL, Special Ed, etc. I have SHiZZA load of Apple IDs. I assume you do to and sometimes we get confused or make mistakes, so just double check.
3rd Close AC, open iTunes, Click store deauthorize and logout of iTunes store, open AC just so it can see that you are not logged in, close AC, Go back to iTunes log backin and re-auth. - Try again with AC
4th Download your spreadsheet again and reimport it.
5th You may simply have corrupted codes. Call support above to check or email for a re-issue.
6th Quit all apps, Run repair permissions
That's all I got. If I was there I could probably fix it. Seriously, though... call for your free support Apple needs to make case logs to document how ****ing crap* AC is.