Use DoEvents
Range ("D5").Select
ActiveCell.Resize(1, 25).Select
DoEvents
SendKeys ("%y1"), True 'Alt+Y1
DoEvents
SendKeys ("%y2"), True 'Alt+Y2, Activates third part add-in
DoEvents
SendKeys ("~"), True 'Enter, initiates the merge add-in function
DoEvents
Range ("D6").Select
ActiveCell.Resize(1, 25).Select
DoEvents
SendKeys ("%y1"), True 'Alt+Y1
DoEvents
SendKeys ("%y2"), True 'Alt+Y2, Activates third part add-in
DoEvents
SendKeys ("~"), True 'Enter,
DoEvents