>Hi,
>
>I have made some changes to the program (nothing major). Then recompiled and rebuilt the application.
>
>Now, at the end of recompile, I get an error:
>

>Visual Class Library d:\applhome\libs\app_flds.vcx has the following errors:
>    Visual Class Library THIS - Undefined
>

>
>The odd thing is that I didn't make any changes to the app_flds.vcx. The library app_flds.vcx has many classes.
>The changes were in some other libraries.
>
>How do you suggest I find the cause of the error above?
>
>TIA
>
>UPDATE. I found where I mistakenly added reference to the OLD VCX library.

Hi Dmitry,
Is it possible the VCX got corrupted? Maybe restore a backup and try again?