Run one macro once a day and another each time at the time of opening the file

Dear Experts,
I want to run a macro 'selection' each time I open the file in a day. After opening the file the focus should be on search sheet cell 'c4' to search new contact details. I create a workbook open event but it gives a error of ambiguous name detected. How to solve it?

Thanking you in anticipation.
Mukesh