USB 634 XP all updates - problem


New member
I've posted this before but time to re-visit it.

I have a usb 634 lcd display thats is set to COM 3 at 19200 baud in both the device manager and the crystalcontrol soft.

During boot the lcd will light up and display the lcd revision information on the screen for a second or two then goes away (as it should) then windows continues to load up. After windows is loaded and crystalcontrol soft is loading i get the message

Int of "COM 3" failed.
The module will be disabled until it is reconfigured.

Heres the catch. And i've tried this a few times.

This message only appears after I apply updates to windows.

With a clean install of windows the lcd works like it should. But after all the updates have been applied the message starts up.

What i have not done is apply the updates 1 at a time to see which update causes this. Some day i might. Till then...... Support team. Time to support.

As for a past suggestion of my power supply not supplying enough power. That is now no longer a problem. To make sure i got a 550 watt power supply.

my system specs are in my previous post.
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New member
Hi !

After updating Windows please try to re-install the USB Drivers for the Crystalfontz Display !