For some reason my Dreamweaver MX has recently started giving me this error when I create a new CSS style:
"Can't find a valid editor for this file extension". Any idea what has caused this?

Here are the steps where I receive the error:
Here are the steps:

Right clicked on page and chose CSS styles/New
Named it .textbox with default settings of Class and NEw Style Sheet
named it mainsite
Then chose the font Arial size 12 and picked a background color.
When I click OK... i get the error.and I click OK
and then it pops up a box that says No Error Occured and I click OK on that.
It will show the name of my style in under my files but it has no extention

Thanks!
Nancy
<font face='Arial'></font id='Arial'>

This issuse is resolved. I upgrared to version 7.1 and it fixed it.
Nancy