VISA serial issues

[RTSLVU]

Recently, I would sa within the last month or two an infuriating problem has cropped up on ALL of my target machines that are Windows 7 or higher.

The serial ports, be they actual hardware add in cards or USB adaptors with virtual serial ports just randomly "disappear" and any LabVIEW program using them gets a timeout error. 

The only way to get these ports "back" is to reboot the computer.

This even affects program that have been running 24/7 for months on end without error, now they could error out several times a day or run for days without issue. NO LabVIEW code has been changed on these systems!

Is anyone else fighting this or similar issue? 

[Dave_Brandt]

Check windows power settings for your usb com ports. Make sure power saving mode is disabled. Windows may be turning off. 

[RavensFan]

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@Dave_Brandt wrote:

Check windows power settings for your usb com ports. Make sure power saving mode is disabled. Windows may be turning off. 

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That's worth looking at, but he said it was happening on actual hardware ports as well, which I would take as real physical DB9's either on the motherboard or on a PCI card as opposed to USB based.