Windows 7 keeps a list of recently used files in C:\Users\<username>\AppData\Roaming\Microsoft\Windows\Recent. Based on my observation, it keeps 10 items for each file extension. So when you So open 11 .txt files in a row, the 2nd to the 11th items will stay in that Recent folder, but the first one will be gone.

My question is: How to keep an unlimited number of items in that Recent folder?

Note: Increasing the per-application recent items (e.g. as in http://www.mydigitallife.info/2009/05/21/change-increase-or-decrease-number-of-recent-or-frequent-items-displayed-in-windows-7-taskbar-jump-list/ ) has no effect on the per-user Recent item folder that I'm concerning.