Why is there an error when launching the form?

Question

Visual Basic

When I run a certain form, the error shown in the screenshot
Why does this happen, it didn’t happen before, but after some time it began to appear.
At the same time, there are no problems with other forms, it is with a certain form

Answer 1

Well, turn on debugging, see which procedure has an error. You start with Form_Load/Open. If not there, you look at the elements on the form.
And the question "why is this happening, it didn't happen before" is useless.
My neighbor’s leg hurts over there, but it didn’t hurt before!