If that is real, tested code, can you please explain what it is supposed to do:

@wslfiles[0]='\\\\XXXXXXX\\f\$\\apps\\webapps\\auth.wsl';
my @wsl = @{$_[0]};
foreach $filename(@wsl)
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If that was not real code that raises the error, then please post short, real code that raises the error (after removing the server name etc.).

From the error message, does the file mentioned in the error message exist?

dir \\XXXXXXX\f$\apps\webapps\auth.wsl
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