I cannot send or receive a .zip file using Gmail.

Gmail prevents users from sending or receiving .zip files. According to their Help Center, only .zip files containing executables such as .exe files are prohibited, but in practice, it appears that all .zip files are not accepted.

Such prohibitions are common among large email providers, and unless they change their policy, the only way around the issue would be to

• rename the file from .zip to, say, .txt or
• use one of the file-sharing services described in Knowledge Base Article 77.