I'm getting the same results as you (on XP 32bit and Win7 RC1 64bit)... however, I have to say, unless I am completely overlooking something, I think the XP results are completely off, and the Win 7 are better, but the errors are not very specific. I tested this with 4.22 and the results were like this way back then too.

There are a number of EnumINIs in the UDF forum, one in particular Glenn wrote... http://www.kixtart.org/forums/ubbthreads.php?ubb=showflat&Number=135385 I notice the way he wrote it, it completely works around this behavior AND actually gives a meaningful error.

I rarely use INI files... but Glenn uses them all the time. I'd be interested in hearing his thoughts.