Vista is now telling me "close programs to prevent information loss": Why?

I just reinstalled vista a week ago (because I caused it to crash three times in two weeks). Anyhow, I have far less information on here than I used to, but I have started getting these messages that say “close programs to prevent information loss.” In that message, it usually recommends that I close Firefox, or Firefox and Chrome if both are running.

I’ve never had this before. Why am I getting it now?

I have a Dell Inspiron 1420, 2GB RAM, and Vista x32.

Do you have your paging file disabled? This is usually a warning that your RAM is running low.

Nope…how do I do that?

Hi gitfiddle. I bet the message says something like “Windows Vista DEP closed this program to prevent …”? This isn’t anything to do with your paging file. Vista self manages that and you rarely need to worry about it.

The key here is DEP - Data Execution Prevention. In laymans terms, parts of the computer RAM is used for storing variables (data such as an Excel spreadsheet, stuff you type in from the keyboard) and part is used for storing programs to run. DEP is a hardware feature that marks each chunk of RAM as either program code (executable) or variables (non executable). In the past many hacks, worms and viruses have tricked the computer into running parts of “variable” RAM as though it’s program code RAM causing a breakdown in system security.

In Vista (and later patches to other Windows versions), Microsoft enfore the DEP flags much more strongly. Lots of system code is marked with DEP. So you tend to get more DEP failures which is what you’re seeing.

All this means is that there are bugs in the programs which are failing. They’re trying to execute code from “variable” RAM. This isn’t necessarily indicative of a hack, just sloppy programming. You can disabled DEP but there is no point. The crashing app will still crash, just a bit later on after it’s really wedged your system!

The easiest way around this is to look for update versions of whatever is closing. Internet Explorer does this quite a lot. It’s generally a plugin such as Flash that’s at fault.

cheers
tim

ps Somewhat informative info from Microsoft here