Single quotes don't interpolate variables. Double quotes do.

use Win32::TieRegistry (Delimiter => '/');
my $version=2.1;

my $key_single = 'HKEY_LOCAL_MACHINE/Software/SPS/$version';
my $key_double = "HKEY_LOCAL_MACHINE/Software/SPS/$version";

print "Single quotes: <$key_single>\n";
print "Double quotes: <$key_double>\n";

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See perlop

In reply to Re^3: Open an application from windows registry by Corion
in thread Open an application from windows registry by ElAlx

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