Help Desk Intermittent Controller Disconnects.
This isn't a software issue, but rather a hardware issue.
- Cable integrity
The first item to check is, of course, cable. If you're using the HCU100/200 USB controller, check the cable and the firmness of the connection, both on the cable side and on the computer side. USB connections, like all removable cable connections, are based upon friction contact. The metal can wear and after time, the connection will not be firm. Even small vibrations can cause a disconnect. This is rare, and most USB connectors are good for 50,000 connections.
If you're using an older HCS type controller with telephone cable and a RJ11 to DB9 adapter/Serial USB adapter, the same hold true. In addition, occasionally, the RJ11 to DB9 adapter will develop and issue and will need to be replaced. This adapter is available from www.telescriptwest.com/Products. Also, the USB2SER adapter is an active electronic device and is subject to the same hazards as all active electronic devices. A repoacement for this device is also available at www.telescriptwest.com/Products. Note that problems with the USB2SER adapter are more often "GO/NO GO", not intermittent. - Device Manager -- USB Power Management
For reasons known only to Microsoft, the USB ports are not covered in your selection of ACP Power Managment, but rather, each USB Device can be suspended independently if there is no keyboard or mouse activity. This clearly happens when you're using the controller.
To fix this, open Device Manager. Most easy way is to use the "Search Box" in Win7 or Win10, and type "device manager". Select the app from the list.
Expand "Universal Serial Bus controllers. For each item in the list, double click, then look for a "Power Management" tab. On this tab, UNCHECK the box that reads "Allow the computer to turn off this device to save power". Click OK and repeat for each item in the list.
Here's a link to a similar discussion on the web, nicely illustrated and annotated:
Disable USB Power Management - Power Options / USB Selective Suspend
In addition, the computer may suspend individual USB ports under a feature called "Selective Suspend". Again, this is NOT affected by your general power settings.
In the Windows search box, type "power options". In Windows 10, you can just right click on the Window Icon (lower left) and select "Power Options", then select "Additional power settings".
For prompting, you should have "High Performance" checked. Click "Change plan settings", then "Change advanced power settings". Find "USB Settings/USB selecting suspend" and select "Disabled".
Here's a link to another article on disabling "Selective Suspend", geared to Win10, but equally applicable to Windows 7:
Disable Selective Suspend
Selective Suspend in Windows 11
Windows 11 can sometimes come configured with no ability to change the Selective Suspend setting. If that is the case, try this:
If you open REG EDIT on one of your problematic Windows 11 computers and navigate to this folder:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\DriverDatabase\DriverPackages\usbport.inf_amd64_cda720c2a7e5ea64\Configurations\OHCI_NOSS.Dev.NT\Driver
In this folder, you will find a file called HcDisableSelectiveSuspend. In the far right column labeled DATA, the correct value should be 0x00000001 (1). If the value is 0x00000000 (0) then you need to change the value to 1. To do this, you will need to right-click the HcDisableSelectiveSuspend and select MODIFY. Change the Value Data to 1 and click OK to save the change.
If you get an error saying you don't have permission to change the value, do this:
Right-click the OHCI_NOSS.Dev.NT folder where the Driver folder for the HcDisableSelectiveSuspend lives.
Click PERMISSIONS. Click ADVANCED.
At the top, you will see the Owner of the registry key we're trying to change. Select CHANGE.
Click ADVANCED.
On the right, select FIND NOW. Scroll down the list at the bottom and select EVERYONE.
Click OK. Click OK in the Select User window.
Click APPLY in the Owner window. Click OK.
Now select EVERYONE in the top part of the Permissions window.
Check the boxes for ALLOW for Full Control. Click APPLY. Click OK.
Now you should be able to change the HcDisableSelectiveSuspend value.