Make Scrollbar Match Textbox Value

I have a scrollbar and a textbox for selecting a value. Everything works fine but it's irritating when someone types 100,000 into the textbox then decides to increment or decrement using the scrollbar. The position of the scrollbar doesn't change with the textbox so (supposing the previous value was 5000 and set using the scrollbar) instead of making adjustments to 100,000 it jumps to 5000 and makes adjustments there.

Private Sub BootstrapScrollBar_Change()

BootstrapTextbox.Value = Format(0, "0")
BootstrapTextbox.Value = BootstrapTextbox.Value + BootstrapScrollBar.Value * 100

End Sub

Private Sub BootstrapScrollBar_Scroll()

BootstrapScrollBar_Change

End Sub

I've tried doing something like making a sub for changes to the textbox with code like BootstrapScrollBar.Value = BootStrapTextbox.value but I keep getting the error "error 308, could not set value".

So is there a way to have the position of the scrollbar tied to the value in the text box?