PCIe 1-port RS-232 Serial Card and USB (IOGEAR) USB to serial adapter quit working.

[JHRing272]

My PCie serial card (Vantec) and IOGEAR USB-to-serial cable quit working.  Neither SecureCRT or Putty will connect.  Unable to access serial port - connection denied even though COMx assignment matches Device Manager status.  All other USB devices work fine including UPS, Label Printer, Fax Modem (StarTech).  I tried updating drivers to latest, I even went into the registry and cleared the Com Name assignment and reconnected the devices one at a time with the same result.  The USB-to-serial cable works great with my Win11 laptop (Lenovo) and with my old HP Win7 laptop, but won't work at all on this tower.  My older TrendNet USB to serial cable quit working with the Z1 Tower as well.   It a nutshell, I have exhausted all avenues to get serial access to my Tower.  I use the serial port to access console ports on network and telecommuications equipment.  The devices work on either PC's.  I even removed the PCIe serial card from the Z1 tower and installed it in an old Win7 PC, and it worked fine.  So did the IOGEAR USB serial adapter.

[BeemerBiker]

There is something wrong with Putty even 0.77  It beeps trying to connect to the console of my EdgeRouter but Microsoft's Simple Serial Terminal works fine***

*** the default Prolific drivers that came with windows needed to be upgraded.  I had to run the chip finder then the driver install

I have no idea why putty did not work.  That SST app (from M$oft store) went and found the device whereas Putty had to be told t use com3

[JHRing272]

Thanks, the chip finder wouldn't open the adapter.  I ran it on my Windows 11 notebook and did find the right driver for the PC2303GC chip set.  I installed that driver, and still it would not work.  Also, my PCIe bus serial board has the same problem,  I can no longer open COM2 (or any other COM port set in device manager) from Putty or SecureCRT.  The IOGEAR USB-serial cable works fine in my Win7 (HP) WIn11 (Lenovo) laptops.  The Vantec PCIe serial card works great in my Win7 HP tower.  Neither will work on my HP Envy Win10 tower.  I even went into the registry and cleared the ComNames entry.  I unplugged all USB devices and plugged in the IOGEAR USB/Serial adapter by itself and it still won't work.  Perhaps a Microsoft Update or a security setting is preventing these two fundamental devices from connecting.  All other USB devices work great.   APC PowerChute, Brother Label Printer, Startech USB FaxModem, to name a few.  I cannot get any RS232 serial port device to work - USB IOGEAR or TrendNet - nor a real PCIe bus connected serial card.  Strange....

[BeemerBiker]

Did you try Microsoft's Simple Serial Terminal?  Putty serial no longer works on my Win11 or Win10 systems

SSH and Telnet work fine, just serial does not find the com3 device, only SST

https://apps.microsoft.com/store/detail/sst-simple-serial-terminal/9P6M6GJSF3HN?hl=en-us&gl=us

[JHRing272]

Thanks, I tried this as well, no luck opening the serial PCIe card that Device Manager says is on COM5.   Device manager says device is working.  I can reboot the PC and maybe 1 out of 20 times it will work.  Something is awry with Windows as if I select any other COM port with device manager, I get a warning that the port may be in use by another process.  Some process is grabbing all the COM ports; however, they do not show IN USE until you attempt to apply the change to the PCIe serial card in Device Manager.  Same thing holds true for the IOGEAR USB-to-serial cable (Prolific(TM) driver).  The IOGEAR cable (as well as another by TrendNet) works great on a Lenovo Win11 laptop, my old Win7 HP Laptop, and my old Win7 HP Tower.  It will not work at all on the HP Z Tower running WIndows 10.  What can I do just short of either wiping the OS and starting over?

[BeemerBiker]

Something I forgot to mention

1 You may need to configure the baud rate using the device manager

2.  Connecting an iPhone or Android may replace microsoft's winusb.sys with any of lib_usb.sys, lib32_usb.sys, libusb-win32/libusb0.sys or libusbK especially if zadig is used to configure USB ports.  This may not apply to you but it happened to me.

[JHRing272]

Thanks, I did set the baud to 9600 to match the management port on the device.   I still have the same problem.  It takes several reboots and some quick action to open the COM5 port with SercureCRT or Putty to open the device.  It's odd, same setup works perfectly every single time with my old Win7 Laptop or a brand new Lenovo Win11 laptop.  This HP Z1 tower works fine with other USB/Serial devices including:

Programmer proprietary serial to USB cable for 2-way radio transceivers (3 different Ones by RT Systems, Inc.)

UPC APS PowerChute Monitor

StarTech USB "Stick"  Fax/Modem

Brother P-Touch Label Printer

The Ones that FAIL consistently with the HP Tower:

VANTECH PCIe Serial Port (Internal to PC) - Only can connect immediately after startup, sometimes.  Device Manager shows all is ok, but applications using device show port unavailable.   Swapped with another PCIe serial board (StarTech) with same exact problem.

IOGEAR USB-to-Serial cable (Latest model)  - same problem as above but works perfectly  on two other PC's (Win7 and Win11)

TrendNet USB-to-Serial cable (7 years old) - same problem as above but works on Win7 PC just fine, used to work perfectly on HP Tower Z1 at one time (Win10).

It seems like any I/O device (USB or PCIe) that delivers and RS-232 Serial port will not work on this WIn10 HP Z1 tower.  All other USB devices work fine.  What changed?  Did Intel Active Management take possession of all RS-232 functions?  Is there some common process that works with physical RS-232 ports (PCIe and USB) that's messed up????

[JHRing272 · Accepted solution]

Update!  I found a terrible workaround.   I connected a US Robotics V.92 fax modem to the PCIe serial port  (set for COM2).  I disabled then enabled the serial port driver then quickly launched the Windows Fax and Scan app.  I then immediately set the Windows Fax and Scan App to "Tools>Fax Settings>Allow the device to receive Fax Calls" .  Now when I boot up the PC, the COM2 port immediately sets the US Robotics Fax Modem up to receive fax calls.  It's like it gets "first to the trough" for COM2 resources.  The serial port at COM2 will stay alive.  To use the serial port without the US Robotics Fax Modem, I go to WIndows Fax & Scan and turn off "Allow the Device to receive Fax Calls"  I then immediately open the port for use with Putty or SecureCRT and disconnect the fax modem and connect it to the console port of the switch I need to configure.  Thus, I fool the PC into hanging onto the serial port through Fax & Scan and then it's available for the console port......

[BeemerBiker]

I am glad you got it working. 

I owned a number of modems working my way up to the premium USR v.92 with voice.

All those lawsuits over monitor screen size and modem speed only made money for the lawyers, raised the price to consumers and put good companies out of business.  I am surprised that auto manufacturer were not sued due to auto not able to reach the top speed that the speedometers panel showed.  Possibly auto unions made a difference.