Welcome to Justanswer.com, my name is ***** ***** I will do my best to assist you.
Ive seen and dealt with this issue before. So I can assist you I need to ask for more information though.
To get started, I need to know what type of computer you're using.
Windows XP, Widows Vista, Windows 7, Windows 8, Or a Mac.
If it's a Mac, please check the OSX version as follows.
Click the apple sign at the top left of your screen, then click about this mac. And then where it says version, send that to me as a reply.
Also, when you access gmail are you using an email client such as mac mail, thunderbird, outlook, windows mail?
Or. are you using the safari browser, internet xplorer, chrome, or firefox?
Please reply with those details and we can begin the process of figuring out whats wrong and solving the issue.