Hi Marcia,
Hi Vladimir,
Hi Martin,

many thanks for your quick answers, all helped, at least to clarify the problem and finally to find the solution. Just read on:

I removed a subdir, which contained a previously saved copy of the form, deleted all *.fxp's and *.bak's, and then recompiled the form.

Then I ran the form, which - among others - contains some buttons, which invoke some methods of the form. In one method I have placed a

Set Step On

I stepped through the code of this method using F8. The debugger showed the code of the method until… Well, somewhere down the code I have a code line

Thisform.AddObject('cntUpperSelector','Container')

which is nicely shown in the Trace window. Some lines further down again Addobject(..) is used, this time placing an object, based on a user defined class contained in a class library, which is accessible. (Without the >Set Step On< this method does its job nicely, so the class lib must be accessible.) The command line is

Thisform.cntUpperSelector.AddObject('NextObject','UserDefinedClassLib')

As soon as the debugger comes across this line, it displays

Source not available

After some experiments and some cups of coffee I found the solution: By hitting F5 I could have the code to continue, but this is not what I wanted. So I made some experiments and finally found it:

Just hitting > Enter + F7 < (Step out) does it!

Have a nice Sunday!

Hans

>Hi Hans.
>
>for some reasons, "suddenly" the Trace window in the VFP Debugger is empty, it just says
>"Source not available"
>
>Re-compile the form.