Problem DLing Adobe Digital Editions v 3.0.4

I have tried twice, unsuccessfully, to DL ADE v3.0.4 and get it to function. The DL went uneventfully, I selected each default option, signed the licensing agreement, ran the exe file, then went to my "desktop", clicked on the ADE icon, and got an error message. I used windows XP to delete the software, then repeated the DL process, ONCE AGAIN following the instructions TO THE LETTER. Same result...error message. NOW WHAT????