With Dreamweaver closed, try deleting the WinFilecache-########.dat or MacFileCache-########.dat, depending on your operating system, file from the following location:
WinXP
-DW8
--C:\Documents and Settings\<Your User Name>\Application Data\Macromedia\Dreamweaver 8\Configuration
-DWCS3
--C:\Documents and Settings\<Your User Name>\Application Data\Adobe\Dreamweaver 9\Configuration
-DWCS4
--C:\Documents and Settings\<Your User Name>\Application Data\Adobe\Dreamweaver CS4\en_US\Configuration
Win Vista
-DW8
--C:\Users\<Your User Name>\AppData\Roaming\Macromedia\Dreamweaver 8\Configuration
-DWCS3
--C:Users\<Your User Name>\AppData\Roaming\Adobe\Dreamweaver 9\Configuration
-DWCS4
--C:\Users\<Your User Name>\AppData\Roaming\Adobe\Dreamweaver CS4\en_US\Configuration
Mac OSX;
-DW8
--Hard disk: Users: <Your User Name>: Library: Application Support: Macromedia: Dreamweaver 8:Configuration
-DWCS3
--Hard disk: Users: <Your User Name>: Library: Application Support: Adobe: Dreamweaver 9: Configuration
-DWCS4
--Hard disk: Users: <Your User Name>: Library: Application Support: Adobe: Dreamweaver CS4: en_US: Configuration
(Please note that <Your User Name> Should be replaced with the User name you use to log into your computer)
Also, please make sure that you have the most recent version of our extensions installed.
NOTE:
On Windows Computers, The AppData or Application Data folders may be set to be hidden.
To View Hidden Folders in Windows Vista:
1) In The Windows Explorer, Click the "Organize" button
2) Select "Folders And Search Options"
3) Select the "View" tab
4) Click the "Show Hidden Folders And Files" radio button.
To View Hidden Folders in Windows XP:
1) On the Tools menu in Windows Explorer, click Folder Options.
2)Click the View tab.
3) Under Hidden files and folders, click Show hidden files and folders.