Error "The PL/SQL language parser must have a rule named Toad_UserTables" in Database browser (4253205)

I've been getting this message "The PL/SQL language parser must have a rule named 'Toad_UserTables'" every time I use the Database browser.

RESOLUTION:

1. Exit Toad
 

2. Go to the Toad App Data Folder
For Win XP it is located in "C:\Documents and Settings\<your_user>\Application Data\Quest Software\Toad for Oracle\<version>\User Files"
For Win Vista and 7 it is located in "C:Users\<user>\AppData\Roaming\Quest Software\Toad for Oracle\<version>\User Files"
 

3. Look for the "LexLib.lxl" file and rename it to "LexLib.old"

4. Then launch Toad again and a new LexLib.lxl should be generated

5. Try opening the Database Browser again