extract data from Non Microsoft application into a userform

Hi All,

I joined this community today. I have a built a userfom for Timesheets in my organization. It has all the required lists and drops downs. But there are 5 textboxes for which the data would be copied from non Microsoft application and paste in this userform before submitting. The other application is always active on the system.

The other application is built on vb6 it seems. its similar to userform with listboxes , textboxes and command buttons. I need to copy data from few text boxes in that application and paste it in my userform.

Can someone guide in proper direction as where I need to start first?

Thank you all.