Same, but it just started happening after I added some more icons to my "default" package. Now when I load the package who knows what is going to go where. Were I to fix this (if it would stick) I would have to redo just about every icon in the package I have... What's up? This happened after I installed the latest update. Version 3.99.146.
I am on XP Pro 32bit.
EDIT: Three of my "homemade" icon packages are now completely fouled up.
EDIT2: To fix this I deleted my 3 icon packages which I used as a real one and 2 test ones. I also deleted the base icon package (the one I used to start with). That had gotten fouled up as well. I downloaded the base package again, installed it and filed in the gaps for the files that didn't have icons with a new package based on the downloaded one. I just saved it as a new package. It's back working again but we'll see how it goes as I add more icons here and there as I find them. It will be a pain if I have to keep doing this.
EDIT3: Just an update a day later. Package is fouled up again. I didn't edit it at all just restarted my computer this morning. IP files now have ini icons, vbs files now have help icons, asp files now have WBA icons and so on. Looking at the package in IP I would say about 25% are out of whack. No ryhme or reason (like the next one over is wrong from the next one etc) just different icons wrong for different file types. Random.
EDIT4: Tried to put the icons back from the same package. Saved it and now about 75% of the icons are off. The only way to fix this to create a new package and add my icons to it for each file extention from scratch as I did in EDIT2.

But I bet once I reboot they will be messed up again. What you guys don't work on Sundays!!!111!! j/k of course.