Original User: thowze
It looks like I'm Johnny-Come-Lately to this thread, and you probably figured it out. I wanted to post this in-case some other poor person was about to throw their computer out the window like I was about to. I was trying to do the same operation of this thread post, iterate through a directory of CAD files, but nothing was happening. I found a solution that worked for me. Silly me, I had the CAD option on the Dataset Type selected, duh. Completely flubbed on that because I thought Dataset Type was a filter for CAD specific layers. I tend to look at Model options to be somewhat logical, so you give me an option of CAD when I want to access CAD files I click it. ESRI meet me half way here! At least document that the dataset type option is there just to frustrate you into curse word filled tirades, then I would only have myself to blame. Turns out, it doesn't like that option, at least not for me, today, at this minute (not guaranteeing the future results or yours for that matter). I deleted that option, put a *.dwg in my wildcard and viola it worked. I really hope this response can help you avoid a disciplinary action write-up from your superiors by reducing any expletives that would come from such nonsense.
Cheers,
Tony