SQL Server, How to set auto increment after creating a table without data loss?

Question

I have a table table1 in SQL server 2008 and it has records in it.

I want the primary key table1_Sno column to be an auto-incrementing col

Answer 1

No, you can not add an auto increment option to an existing column with data, I think the option which you mentioned is the best.

Have a look here.