Users of Microsoft’s Internet Explorer 8 who use Gmail or Google Calendar will soon have to upgrade or switch browsers, as Google Apps is dropping support for the aging browser on November 15.

On October 26, Microsoft will release Windows 8, and with it, Internet Explorer 10. As Google Apps are only supported on the most recent release of a browser and the major version prior to it, this means that support for Internet Explorer 8 will end. Here’s what the team has to say:

As we announced last year, we support the latest version of Google Chrome (which automatically updates whenever it detects that a new version of the browser is available) as well as the current and prior major release of Firefox, Internet Explorer and Safari on a rolling basis. Each time a new version of one of these browsers is released, we begin supporting the update and stop supporting the third-oldest version.

Internet Explorer 10 launches on 10/26/2012, and as a result, we will discontinue support for Internet Explorer 8 shortly afterwards, on 11/15/2012. After this date users accessing Google Apps services using Internet Explorer 8 will see a message recommending that they upgrade their browser.

For users of Windows Vista and newer, this simply means that they need to upgrade their browser. For users of Windows XP, however, the process is more complicated, as Internet Explorer 8 is the most recent version of the browser currently supported on the operating system, which turns 11 years old next month.

This affects a greater number of people than you may think. According to NetMarketshare, Windows XP is still used by 42 percent of the market worldwide. Windows 7 just barely gained the lead on it last month, and even then only by a margin of 0.24 percent. To remain supported, Windows XP users will need to either switch to a different, supported browser, or upgrade their operating system.

Being unsupported doesn’t mean that users of the older browser will suddenly be unable to use Gmail or Google Calendar, but they may encounter issues. Apps like Google Drive and Google Docs are much more likely to have issues or not work at all, and Gmail’s new look is unavailable on unsupported browsers.

Those who absolutely have to stick with Internet Explorer 8 may have better luck with Google Apps by installing Google’s Chrome Frame Plugin, but this hasn’t been commented on by Google.

Are you or someone you know going to be affected by this change? If so, what do you think you/they are going to do?