This year, Gmail will no longer work in the Chrome browser for Windows XP and Vista
The online interface of Gmail with the following environment will begin to show a warning about the termination of support of old versions of Chrome. To continue to use email, you will need to update Chrome to version 55. It is associated with significant changes concerning safety.
Unfortunately, the above solution is not suitable for users of Windows XP and Vista as Microsoft has discontinued support for these operating systems and update Chrome for them was stopped after version 49.
If you do not update OS and browser, Gmail will continue to work almost to the end of the year. However, in December, service will begin to redirect users of Windows XP and Vista to the basic HTML version of the interface with a lower level of functionality and protection.
Source: G Suite