Corel Draw 9: Error writing in coreldrw.cdt file

CDT is a template file. If you do file > new from template then the contents of the template are copied into the new file. But I think CorelDraw probably use a default template when you create a new file without specifying a template.

I guess the first thing to do is to check if the specified c:\Program files (x86)\corel\graphics9\draw\coreldrw.cdt file exists and try if possible to get a copy of that file from another machine that runs version 9.

If not, the F8 reset may fix it. Close CorelDraw and hold the F8 key down while restarting CorelDraw with the mouse, keeping it down until you get a message confirming the reset.

There is a downside with doing this -- any special settings you have made will be lost and it may not necessarily recreate the default template if it is broken. But it is a quick way to revert CorelDraw to standard settings and does fix many problems.