Problems unzipping computer training exercises

Some people have reported that they can not unzip exercises that they've downloaded from our website.  Here's what we know about this!

Our zip files are created in a .NET application, using a utility called SharpZipLib.  We can happily unzip anything created in this, using either computers running XP or Vista.

If you experience problems unzipping, some people have reported that WinRAR gets round them.  We don't endorse this product, but it's certainly worth trying.

If anybody either knows more about this issue or discovers more, we'd love to hear from you.