Just thought I'd throw this out here and see what happens...

On my Vista Ultimate machine I'm having trouble unzipping files.
It takes FOREVER to unzip even a 2 or 3 meg. file.
I've dug around and had one suggestion that anti virus
software could cause this problem. I use AVG and
disabled that with no change.

Anyone here familiar with this problem? I'm new to the site so
forgive me if I missed the answer somewhere else.

Try using winrar. It's a always free (even though it says trial) and it can read and compress alot better then using the zip in windows vista or XP.

http://www.rarlab.com/rar/wrar371.exe <- download link

You might want to try 7-zip as well. Open source available from SourceForge.

 http://www.7-zip.org/

Have your tried installing the compatibility and file system copy updates that Microsoft has released in the last month or so?  There have been some improvements in explorer file operations, and it might help you're situation.  They will be part of SP1, but are available from Microsoft's website now.  I've installed them all, and while they don't perform miracles, I do think they help.  And I haven't seen or heard of any side effects.

 For a third part option, I like 7-zip personally.
 

Thanks Xtreem0 and 7glr for your suggestions and links!

bsieker,

I guess those updates are not included with the regular Windows Updates? Hmm...
I'll check Microsoft for the updates you mentioned and see what happens. It seems not everyone
is having this problem with their Vista machines. That makes me think it's something insidious that
I've done by mistake. Anyway I'd like to find a solution as to what's causing this. It seems like you
should be able to use the available zip technology that comes with Vista. That's not to much to ask is it? ;-)

I believe as far as zip programs go, there are only 3 to download. The tried and true WinZip, although it has problems with .gz format. 7 zip I have recently use and like very much. Also Winrar is pretty good too. I think Microsoft needs to be briefed on this and expand the zipping capabilities in the next OS release. Paul, you should bring that to Microsoft's attention.

The thread is full of good suggestions for alternatives (I used the WinZip one), but it doesn't get to what actually is the root of the problem. I have the same issue! What IS IT that causes this and how can we fix it at its origin?

The other thing which is similar and may be related, is that I.E. downloads seem to proceed swiftly like always until it says 99% finished, then it sits there and won't move to DONE for nearly 3 to 5 minutes, just like the UNZIP problem. Makes me wonder if the Explorer protion of Vista has a bug that affects Internet Explorer and unzip resolves. 

wingtouch,

Along with the unzip issue I also have the problem you speak of. Although my delay is more like 1 or 2 minutes after downloading.
Even though these are frustrating problems I'm glad to see they are not just happening on a few systems, but most of them. It is
surprising that Microsoft has not fixed this yet. All one needs to do is Goggle this and you see how many folks are suffering.

On the unzip question, I installed 7zip and that thing works great. 20sec to unzip a 550meg file.

On Vista in general I'm very happy with it overall. They have fixed many of the problems since the release. I'm sure we will
see these resolved soon.