Keystrokes lost--space weirds out Mail

Question

Just in the last few days, whenever I try and compose a Mail message I get the following *really weird* problem:
When typing in the subject line, every space I type becomes two.
When typing into the body of the message, as soon as I type any space a) the blinking insertion point disappears and b) no type is visible from then on.
**Other typing?
My typing works 'zactly as't should in every other app I've tried (Word, TextEdit, Safari, etc) except SOHO Notes where typing does not appear in a Note I create or edit but when I quit the app and open it again then all the typing appears.
**Stuff I've tried:
Creating a new Mail account in a new login: worked like a charm.
Removing the Mail folder from the ~/Library directory and creating a new mail account: Still had the problem.
Checking for updates (I have v2.1.1 and there are no updates.
Restarting: still bad.
Simplifying (having only Mail open): still bad.
**Further Notes
I've turned on Keyboard Viewer and all the keystrokes appear as they should (including just one space for Subject Line typing).
I gots no idea what's what. I don't recall any updates / installs at the same time this problem started.
Copying and pasting text works great.
Help!
Please e-mail me directly at [email protected] as I don't get to these forums often.

Answer 1

This problem could be related to the built-in spell checker, and be caused by some Launch Services cache or preferences corruption. The following article describes how to manually reset Launch Services -- the notes at the bottom of the article also provide information about the side effects of deleting each of the files involved:
Resetting Launch Services
If you prefer using a cache cleaning utility instead of following the manual procedure described in the previous article, this other article provides links to some utilities that can be used for troubleshooting and cache cleaning:
Resolving Disk, Permission, and Cache Corruption
It seems that the most appropriate utility for solving this particular problem is Tiger Cache Cleaner, but you may also want to consider other utilities, such as OnyX, or Cache Out X, which are free. Whatever utility you choose, be sure to read this first:
Side effects of System cache cleaning
As an example, this is how you should proceed with OnyX:
1. Quit all applications.
2. Launch OnyX and enter your administrator password.
3. Click Maintenance. In the Reset section, check LaunchServices database.
4. You may uncheck any other pre-checked options if you wish.
5. Click the Execute button.
6. Restart the computer.
Please e-mail me directly
That ain’t gonna happen. It would defeat the whole purpose of these forums. Moreover, publicly posting real email addresses here is a really bad idea.