Firstly - you have a syntax errors in your SQL...
"UPDATE EMP_MASTER ) "
Try removing all of those extraneous brackets and putting in some extra commas
UPDATE EMP_MASTER
SET Sap_No= @Sap_No, CPF_No= @CPF_No, Name = @Name, Designation= @Designation, DesigIndex= @DesigIndex, CompJoining= @CompJoining,
TPSJoining=@TPSJoining, QtrNo= @QtrNo, DOB= @DOB, DOR= @DOR, BloodGroup= @BloodGroup, MobileNo= @MobileNo, CLAvail= @CLAvail,
FLAvail=@FLAvail, CLBal= @CLBal, FLBal=@FLBal, EmailID= @EmailID, Status=@Status where Sap_No= @Sap_No ;
Next question is obviously, is there actually a record with
sap_no
with a value that's in the txtSapId textbox? One to watch out for as you are assuming that an integer has been enetered into that text box
On another note, all those Txt....
Text.ToString()
... the .ToString() is unecessary, you are literally saying "convert this string to a string"