Adding file extensions recognized by Dreamweaver MX

[user@domain.invalid]

I followed instructions from Macromedia's web site on how to add the
extension ".inc" to Dreamweaver MX. Before doing this, include files
could only be viewed in code format. The instructions have enabled me
to now view include files in design mode, however opening Dreamweaver MX
gives me a series of error messages such as:

"The Document Type "HTML" will not be added because it uses a file
extension that is already associated with a prior Document Type."

Next is "JavaScript", then "VBScript", etc.

These are all the extensions recognized by Dreamweaver and when I added
"INC" to the list, it must think everything else in the file is a
duplicate. If I revert the two files back to normal, things are as they
were. Any suggestions on getting rid of these error messages? Oh yeah,
this happens when using a PC. On a MAC, the troubleshooting suggestions
don't work at all. I am interested in finding a solution for both a MAC
and PC. Here is the troubleshooting page from Macromedia's web site:

[url]http://www.macromedia.com/support/dreamweaver/ts/documents/add_ext_mx.htm[/url]

Thanks,
Jason

[JREYES-MMTS]

Hi Jason,

It sounds like you have made a backup of the original file in the same
directory. Trying moving your backup to a different directory. The error
should go away then.

Hope this helps,
Jaybee Reyes
Macromedia Technical Support