During the installation of Macromedia ColdFusion MX, the filecf_root/lib/typeviewer.dll is registered on Windows platforms. If it is unable to successfully register the file, you will receive the following error when calling COM objects throughcfobject or createObject:
----- An exception occurred when instantiating a Com object. The cause of this exception was that: AutomationException: 0x80040154 - class not registered. -----
COM objects must be registered within Windows in order for ColdFusion to find them. If they are not, you will receive the error above. If the COM object has been registered, either manually or through a setup program, but you still receive this error, it may be caused by cf_root/lib/typeviewer.dll not being registered successfully.
You can use two methods to determine ifcf_root/lib/typeviewer.dll was registered successfully during the installation of ColdFusion:Windows RegEdit