I have a digitizer attached to COM 1 (serial) at all times. Sometimes it works fine, but sometimes it will go out, apparently for no reason. Re-booting doesn't work-the only way to get my COM 1 back is to go into Device Manager and uninstall it, then restart. I've talked to HP and the manufacturer of the digitizer, neither one can tell me why this happens, sometimes in the middle of digitizing. Any ideas? Thanks in advance.

In BIOS you can assign a different address range for COM 1. Try that. Regards SuatCINI

Not sure what that means. I have a little knowlege of computers, but I try to stay out of BIOS. Can you elaborate? Thanks

Not sure what you mean. I have some general knowlege of computers, but no experience with BIOS. Can you elaborate? Thanks

Different BIOS manufacturers may have different wording for the same settings. In my BIOS, The "Integrated Peripherals" has the place where you can change the setting I was talking about. It reads Onboard Serial Port 1 in Integrated Peripherals. The possible settings are Auto 3F8/IRQ4 (Default value) 2F8/IRQ3 3E8/IRQ4 2E8/IRQ3 Disabled Therefore, you have 6 options including Disabled. You do not want to select Disabled. My default setting is 3F8/IRQ4. If this is also your value and it is giving you problems, then choose another setting and try until you find a setting that does not give you any problem with either the device connected to the serial port or any other device installed in your PC. Do not be afraid of playing with different values. This is not BIOS flashing thing. You can always change the setting back any time. After selecting a value, you must save the changes and exit and boot into Windows. If everything works the way you want, then stay with that value. By the way, do not choose a value that is assigned to Onboard Serial Port 2 by default. Hope the above helps. Regards SuatCINI

Check in cmos/bios setup for a 'PnP OS' option. Set that to 'NO'. If it's the OS that's disabling the com port then setting PnP OS to NO should stop it.

Just thought I'd add some info to previous posts. It may not matter in this case, but the different address/IRQ settings in BIOS dictate which COM port # the computer's onboard serial port takes. For some hardware/software this can make a difference. If your BIOS does have selectable address/IRQ like suatcini described previously, then your serial port will become COM1-4 based on which address/IRQ you select in this order: 3F8/IRQ4 = COM1 2F8/IRQ3 = COM2 3E8/IRQ4 = COM3 2E8/IRQ3 = COM4 So, if your digitizer (more specifically, the software driver for your digitizer) expects a particular # COM port, then your PC's serial port will need to be set to the correct address/IRQ. Usually, when left to AUTO, and running a PnP OS, the single serial port will be set to COM1 during boot up.