Many of you have been exposed to the registry in Windows XP, the database that holds all of the information, settings, and options for the computer hardware, the Windows OS, and most programs. It can be manually edited using REGEDIT.EXE or REGEDT32.EXE and there are lots of online instructions about how to change this or that in the registry to fix a program or remove spyware or change a Windows feature or the like.

Having said that, I have to add the obligatory – and dead serious – disclaimer.

danger Careless registry editing can cause irreversible damage to your computer. Do you see the word “irreversible”? Do you have it clearly in mind? You can kill your computer in seconds by mucking around in the registry. Don’t go there unless you are 100% sure of what you’re doing.

The registry is big. Really big. The kind of big that means even if you’ve looked at it, it’s bigger than you realize. I’d been curious about that but there’s no easy way to see how much information is in the registry.

Here’s the results of an experiment by a tech guy – he exported his entire registry into a 139Mb TXT file, then tried to open it in Microsoft Word.

It exceeded the maximum page count supported by Word, which crashed when it got to 32,767 pages of plain text.

He kept working and got a different word processor to paginate the file up to page 39,721 before it used up all its virtual memory and died.

And the punchline comes in a comment to the blog entry today, written by someone else who repeated the experiment and found a word processor that could open the entire text file, displaying all the contents of a typical Windows XP registry. He doesn’t give a page count, but the file has 2,566,276 lines of text.