If you are having trouble downloading your gmail into Outlook or another mail program, or on your smartphone, it may be a problem on Google’s end:
According to the “known issues” page on Google’s web site:
We are aware of an issue where users are receiving an error that ‘"imap.gmail.com" is not responding’ when using IMAP on their computers, mobile devices, or tablets. We are currently working on resolving this issue. In the meantime, you can sign in to Gmail through a web browser. For Android and iOS users, you can also download the Gmail application in the interim.
Here’s a link to the “known issues” page: