I have a windows .exe file, but the source code for it is missing. The developer was not responsible and left our company. I think it was a delphi/pascal program. The develop
One application that lists the used units in a delphi binary (similar to RRUZ's demonstration), is XN Resource Editor. Latest version is here AFAIK. The below sample screen shot for instance (by luck :)), points to a particular 3rd party library:
As 'Worm Regards' suggested in the comments to the question, the application also displays 'dfm' contents, hence one can see the class names of used components. But for that, I'd suggest DFM Editor, because this application displays the used components in a tree structure, much like the 'structure pane' in the Delphi IDE:
XN or any other resource editor can be used to export a dfm resource to a file, to be examined with DFM Editor.