We solved the problem by giving admin rights. However, this is not a solution our IT staff is comfortable with. I ran into similar issue as you. The problem was that one of the admin built the pc image and somehow ArcGIS Explorer use the cache folder under that admin account for cache folder for everyone. When a non-admin user were not able to write to cache folder to a admin account, ArcGIS Explorer complains with a confusing message. Solution: 1) Go to ArcGIS Explorer Options which is under the upper-left globe 2) Select Advanced 3) change the cache folder to go to the non-admin user folder Good luck.
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