Change your query from
string strQuery = "INSERT INTO [Register],[firstname],[lastname],[email],[Password],[Gender],[Dob],[Mobile],[department],[Address]) VALUES (@firstname,@lastname,@email,@Password,@Gender,@Dob,@Mobile,@department,@Address)";
To
string strQuery = "INSERT INTO ([Register],[firstname],[lastname],[email],[Password],[Gender],[Dob],[Mobile],[department],[Address]) VALUES (@register,@firstname,@lastname,@email,@Password,@Gender,@Dob,@Mobile,@department,@Address)";
you are missing "(" bracket and @register parameter.
Updated 21-Jul-14 2:44am
v2