Kevin,

1) start by debugging it as a normal VFP class oX = createobject( "TheClass" ) once that works

2) debug it as a COM oXCOM = createobject( "TheDLL.TheClass" )

both these will allow you to fully use the debug facilities of VFP.

Then you have to debug it as a server which might surface a whole host of problems because the DLL will operate in an enviroment that is different than your dev time environment.

To aid server debugging you can use a logical property to control output to a text file that can be viewed in IE while your code is running. You can use a simple click of the refresh button to get the new output. Or use Notepad which will not hold a hard lock on the file, you can not use Wordpad or VFP to view the file because the file can not be written to while they have the file open.

if ( this.lDebug )
   strtofile( "now I'm doing this " + program(), "c:\temp\TheDLL.txt" )
endif

>How do I debug a DLL?