I just received an error message from gmail informing me that their antivirus scanners are inactive. Hence an email attachment that I just received had not been scanned. What to do? Is it safe for me to ignore the error message since am using a Ubuntu machine?
Generally, Linux systems have been designed so that opening an attachment has no by-effects: the program you open the attachment with will process the attachment as data only, and will run no commands or programs it has no control of.
In theory, there may be a bug in this defense system that the attachment is targeted to use. This is very rare though. The rule of thumb here is: don't open attachments from parties you don't know and that you didn't expect to receive.