A Closer Look at the Windows Vista Registry - dummies

A Closer Look at the Windows Vista Registry

By Woody Leonhard

The Registry is Windows Vista’s central repository for all sorts of different settings — the name of your keyboard driver, the size of your desktop, the location of the program that plays MP3 files, and tens of thousands more items that control Windows. The Registry is a big, dark, spooky place full of peril and hidden pitfalls. Kind of like IRS Form 1040. But if you know how to work with the Registry in Windows Vista, you can have much greater control over how your system operates.

Most people go into the Registry for one of three reasons:

  • They read on the Internet that if you change some Registry setting, your copy of Windows works better or faster or both.

  • They have a specific problem that Microsoft says can be fixed only by manually changing a Registry setting. Unfortunately, this type of Registry editing is on the upswing. The MS Knowledge Base is packed with articles that require changes to the Registry.

  • They have a specific problem that Microsoft doesn’t talk about, but experts know it can be fixed by changing Registry settings anyway. For example, a lot of Registry tweaks force Windows to bypass some of the senseless security restrictions in Outlook.

Nobody completely understands the Registry. Nobody has ever pulled together a complete description of what all those settings mean. The items are infuriatingly inconsistent, generally entirely undocumented, and stored away in a very nearly random order. It’s never a good idea to go into the Registry to “fix” something if you don’t know precisely what needs fixing and how.

How the Registry works

The Windows Registry may look like a file or a database, but it’s really a conglomeration of many different pieces drawn from several places. You can change some of the entries, but other entries are generated by Vista internally and are off limits.


The Windows Registry has grown up in a hodge-podge way, and so terms that (arguably) made some sense back in the day don’t mean baloney now. Microsoft has put absolutely no emphasis on maintaining consistency inside the Registry. Like a teenager’s closet, you never know what you’ll find in there, and any resemblance to organization is entirely coincidental.

You can add or delete folders in the Registry Editor just like you can add or delete folders in Windows Explorer, but that’s where the similarities end. You can move a folder in Explorer, but you can’t move a key in the Registry Editor. And when you delete a key in the Registry Editor, there’s no Recycle Bin to help you recover from your mistakes. After you delete a key, it’s gone.

Modifying Registry values

Almost all the changes you make to the Registry involve modifying values: changing, adding, or deleting values (although once in a very blue moon you may need to add a key). Each value in the Registry has a name and data.

When you modify Registry entries, make sure you use the right data type for the value’s data. For example, if the value’s data is supposed to be a number, and you type in a bunch of letters, you can mess up everything. That’s why it’s very important that you follow instructions for changing the Registry quite precisely.

Here are the three most common types of value data that you encounter in the Registry. Make sure you stick to the type of data that the value requires:

  • String: Characters — letters, numbers, punctuation. Anything you can type on the keyboard is fair game. This is the best kind of key because it’s hard to mess up!

  • DWORD: A “double word” 32-bit (4-byte) integer between 00 00 00 00 to FF FF FF FF in hexadecimal. When you type in DWORD data, use only these characters: 0 1 2 3 4 5 6 7 8 9 A B C D E F. You don’t really need to understand that an A is 10 in hexadecimal, but it doesn’t hurt.

  • Binary: Similar to DWORD, but binary data can be any number of bytes long. Throughout the Registry, many strings are stored as binary data. In many cases, you have to be very, very careful when you change binary data so that you don’t change its length. Follow your instructions precisely and keep track of the binary data’s length.