I had this problem before in Excel 2010, so there is no reason it is not working.
1. Make sure that personal.xxx is not in disabled section of Add-in.
2. Go to ur trust centre and make sure that user auto start and excel auto start is pointing to valid folder.
3. Make sure whatever file u want to load is there.
For me, my file is personal.xls (dunno why still in old version) and resides in user auto start.