Okay, you send, I Learned.
You brought me a idea to solve this problem I saw there was a button in the excel sheet. It was working real fine, but not mend for me. So, I did the following in my Access 2016.
I created another textbox, (like a dummy textbox) with the name (which you choose) I've called my textbox "txtTarget"
In the properties of that textbox under the tab Data, I put the following.
Recordsource =0
Locked = true
enabled = true
The properties for the new textbox must be the same as first textbox. (see tab formatting)
Private Sub Form_Open(Cancel As Integer)
Me.txtTarget.Visible = False
If Me.txtSaldoWH1.Value >= Me.txtTarget.Value Then
Me.txtSaldoWH1.BackColor = RGB(0, 255, 0)
Else
Me.txtSaldoWH1.BackColor = RGB(255, 0, 0)
End If
It works like a charm, because you set me on the right track to solve this problem.
Many thanks,