I would be suspicious of your definition of $file and $filename. 
my $file = 'SyncItemMaster.xml';
my $filename = 'Hashstructure.txt';

[download]
is more what I would expect to see, though I am unfamiliar with what you are trying to do...

In reply to Re: filename flagged as Invalid argument by jonnyfolk
in thread filename flagged as Invalid argument by Mr.Churka

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