What would produce these strange characters in a DateTime to String conversion?

I have some code which records a DateTime in some output files:

 DateTime dateTime = DateTime::Now;
 String^ value = String::Format("{0} {1}", dateTime.ToShortDateString(), dateTime.ToLongTimeString());

...which is apparently giving some odd outputs on a customers machine:

2014-12-16 오전 12:00:00

What might be causing those additional characters to appear there?

Jon Skeet
people
quotationmark

That's fairly reasonable if the user is in a different locale - you should ask your customer what their system locale is. Use the invariant culture if you want a machine-readable format. For example:

String^ value = dateTime.ToString("yyyy-MM-dd HH:mm:ss",
                                  CultureInfo::InvariantCulture);

people

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