Some older email systems are not capable of receiving binary attachments (zip files are binary attachments). If you wish to email them your zip files, you can do so by first encoding your zip files into plain text. This is called UUEncode. To do so:
1. Select the zip file you want to encode (click on its drive icon).
2. Click Tools->UUEncode Chosen Zip File.
If you receive such an encoded file, you will need to decode it before you can use it. To do so: