>   my $respons = $response[$i][$j]{creden}{uName};

That's supposed to be the line causing this error?

No way...

Help us to help you by providing more insight.

update

the only possibility I see is auto-vivification of non existent entry "creden" provided $response[$i][$j] is read-only. (if that's even possible)

A prior check would solve this!

update

though the error messages don't match. 

  DB<72> $a{1}=\1

  DB<73> use warnings; say $a{1}{foo}{bar}
Not a HASH reference at (eval 81)[c:/Perl_524/lib/perl5db.pl:737] line
+ 2.

[download]

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery

In reply to Re: Modification of a read-only value attempted by LanX
in thread Modification of a read-only value attempted by chandantul

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