A cookie is small data files written to a user’s hard drive by a web server. These files contain specific information that identifies users (eg, passwords and lists of pages visited). For example, you sign in to a forum and there’s a checkbox where it says “Remember Me” or something similar to that. Once you enter your log in information and check on that checkbox, a cookie file will be saved on your computer. So the next time you visit that forum again, you won’t need to enter your username and password. You wouldn’t want your username and password saved on a public computer, so it’s best to manually delete all caches and cookies after using a public computer.
Well, fortunately cookies do expire. Once they expired, you need to enter your login information again. The expiration usually depends on the web server. The expired cookies are useless and will take up your disk space. It’s very small, but it’s always a good practice to delete unwanted files on your computer or else one day your computer will be filled with too much junk!
Deleting cookies from Internet Explorer options like the picture below deletes ALL cookies.

So how do you delete only the expired Internet Explorer cookies?
Expired Cookies Cleaner is a freeware program for removing expired cookies from you personal computer (PC).

Microsoft Internet Explorer (IE) stores cookies in different files on your hard disk drive. More you browse the web, more cookies are stored on your PC. Each cookie has its own lifetime – from several seconds to several years. However, IE does not remove expired cookies from your PC even they are expired and will be never used. Therefore, your hard drive can store several hundreds or even thousands unused and useless files.
You can use Expired Cookies Cleaner software to remove expired cookie files and speed up your PC and free some disk space (especially on FAT and FAT32 file systems).
You can also use Expired Cookies Cleaner from the command line without GUI. Just add parameter “a” character at the end of the command line. For example:
C:\>ExpiredCookiesCleaner.exe a
In this case program saves all output in the file Result.log.
[ Download Expired Cookies Cleaner | Expired Cookies Cleaner Website ]