I searched on this topic online and it appears that ESRI has had the same problem in the past. It appears to be happening again. I have an organization license of ArcGIS and go to load simple shape files (zipped) and the error message said the files is too big and unable to load. Not sure what else to do. I am using Safari and one of the files is only 183k- yep "K".
Any help would be appreciated.