Put file names (not handles) in @ARGV: 

my $new_par = "YI_OU";
local $^I = '';
local @ARGV = 'c:/perl/test/1.txt';
while(<>) {
   s/UI_EM/$newpar/g;
   print;
}

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In reply to Re^3: $^I why this symbol does not work ? by ikegami
in thread $^I why this symbol does not work ? by kingwrcy

Title:
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