first i try to explain  what i had tested application, with 
help of tracebility matrix. after that he cannot convince i 
will try to let him know like some defects are not found in 
during testing, that type of defects founded by the clients 
at longtime usage of application. its cannot findout at 
shorttime(testing.so that defect updated in future versions

if it is wrong correct me

a)	1st I will check the defect I executed or not
b)	2nd I will check the given trace ability matrix 
that test data is given or not
c)	If that defect in my build or next build I verify
d)	That defect in new Addison after coming or not I 
will check
e)	If that defect I am found that time the developers 
solved remarry or not I will check
f)	This like some conditions I will checked
g)	After the above the conditions I will try to 
convince to my team lead and customers


My name is k.chandra sekhar
My phone no is 09246540049
I am in hyderabad
My mail id is ndra_143@yahoo.co.in

Its a very simple thing

- Communication is the key,report to the TL that it has
indeed been defect, but since not a showstopper, it can be
later on taken into Regression
- Customer should be told that regression testing would
happen and we will make sure to get rid of the defect
- Own the responsibility that the issue would be given a
priority
- Go through the documents properly and also the test cases
thoroghly

First check whether the test environment used by client and 
you are same.Then check whether you have test case covering 
this scenario.

-If your company is following proper processes, no one can 
come to you.Because, BA would have reviewed the test 
scenarios, HLTCs.Your peer would have reviewed the test 
cases written by you.

-IF there is a test case covering the defect raised by the 
customer, then the execution would have not happened 
properly.If you have made some mistake while executing the 
test case,just explain your TL how you have executed the 
test case and own the responsibility.