I had the same thing happen to me. I emailed tech support and apparently there is no way to remove that evidence of a failed transfer. I took a bit of a drastic measure and uninstalled/reinstalled all the EyeFi software. The trick (for me, running on Win7 x64) was to delete some temp directories under C:\User\xxx\AppData\Local and Roaming. Don't quote me but I "think" the evidence of a failed transfer is stored there somewhere, because after I uninstalled the software, deleted those directories, and reinstalled the software, the palm trees went away.
I hope someone else chimes in with a better solution, although I've gotten pretty good at uninstalling/reinstalling.