Just to make sure that the school's software security isn't the issue, I tried uploading and downloading a .zip file from home. Same result.
1. I can zip and unzip at home on my computer.
2. I can upload the zip file to Moodle.
3. I can post in my course.
4. I can download the file. It's file size appears to be correct.
5. When I try to unzip it, the error message says there are no files to extract.
Would someone using Windows XP please zip a set of folders and files, add it to your files collection in Moodle, post it as a resource, and then download it back to yourself?
Thanks so much.