HowTo repair Win 7's zip? (solved)

[Curt]

I was just writing a very frustrated letter to a company because each and every zip folder from them were rejected by Windows 7 as being not-valid, when a bell started ringing in the back of my head. I aborted the angry letter, right-clicked some of the zip containers, clicked "7-Zip... Unpack to "...", and voila! the zipped containers were all just fine.

So, my (64-bit) Windows 7 (Home Premium) unzipper has broken down, and I have absolutely no idea what to do to repair it. The file association is still okay; "Open in Explorer". I have never used Windows to create a zip container, but I use it every day to unpack single containers. If I have more containers, I always use 7-Zip, but for a single container, I always use Explorer.

Any suggestions on what to do (to repair it), please?  

[Renegade]

I'd ask them what software they were using to create the ZIP files first. My initial reaction would be to assume that the ZIP files are the real culprits, and that 7-zip simply has better error checking than the default Windows zip program.

Otherwise, this might help as a starting point:

http://superuser.com/questions/149489/does-windows-7-have-unzip-at-the-command-line-installed-by-default

http://pcsupport.about.com/od/findbyerrormessage/a/zipfldr-dll-not-found-missing-error.htm

[40hz]

Much easier to just make 7-zip the default program for ZIP files and not worry about it.

[x16wda]

Much easier to just make 7-zip the default program for ZIP files and not worry about it.

Yeah... remediate or mitigate, fix or work around... it's always a question of which wins.  In this case I vote the same as 40hz, especially since I could always dig into it later.

That said, Curt, does Windows handle zip files from other sources ok?  Can you create a zip in Windows (or in 7-zip) and open it successfully in Explorer?

[Curt]

... My initial reaction would be to assume that the ZIP files are the real culprits, and that 7-zip simply has better error checking than the default Windows zip program.

-this seems to have been the right answer. Nothing is wrong now.

Thanks to all of you for trying to help.