I'll admit, that's not one I've ever seen before. Where/when does it occur? List all the files you transferred, especially their file extensions. If you can't do that, maybe it's just best to delete them and redownload the files from their proper places.
by the way:
.x86: intel binary (linux also uses this extension, but linux .x86s won't run on a mac)
.ppc: PowerPC only binary. Runs on an intel mac with emulation (i.e. slower)
.ub: Universal Binary. Runs at full speed on both types of mac.