in reply to Re^3: Using 64 Bit Perl for Production Scripts.
in thread Using 64 Bit Perl for Production Scripts.

That suggests your machine simply does not have serial ports configured.

To verify, run msinfo32.exe; click Components->Ports->Serial.

In the context of this thread, the usability of Win32::SerialPort under 32 & 64 bit Perls is telling you nothing useful.

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