After a disassembly and re-assembly,the USB connections no longer work

Roger, check first what Microsoft suggest:" Step 1: Run the hardware and device troubleshooter.

http://windows.microsoft.com/en-us/windo...

Step 2: The key to all USB devices is the firmware. The USB device's firmware contains all information about the device. A port is not reset until all descriptors in the firmware have been loaded and verified by the root hub.

Make sure that you have the most up-to-date firmware that is available for both your computer's BIOS and each device.

http://windows.microsoft.com/en-us/windo...

NOTE: Modifying BIOS/complementary metal oxide semiconductor (CMOS) settings incorrectly can cause serious problems that may prevent your computer from booting properly. Microsoft cannot guarantee that any problems resulting from the configuring of BIOS/CMOS settings can be solved. Modifications of the settings are at your own risk." from here. Or you can also try this:" First, please disconnect all USB devices and then perform the following steps:

Using the mouse;

1. Click "Start" button, type “devmgmt.msc” (without quotes) in the “Search” bar and press "Enter". Click “Continue” if necessary.

2. In Device Manager, double click to expand "Universal Serial Bus controllers", right click on the Host Controller, click "Uninstall" and click "OK".

3. Repeat the step 2 to uninstall all items under "Universal Serial Bus controllers".

Then, restart your computer and Windows 7 will reinstall all USB controllers automatically.

Using the keyboard;

Again, disconnecting all USB devices

1. Press "Ctrl + Esc" to open the “Start” menu.

2. Type “devmgmt.msc” in the Search bar and press "Enter". Click “Continue” if necessary.

3. In Device Manger, press Tab and use "Up" and "Down" to move the highlight to "Universal Serial Bus Controllers".

4. Press "Right" and expand it.

5. Press "Down" to move to the first item and press "Delete" to remove it.

6. Repeat the step 5 and uninstall all items under "Universal Serial Bus Controllers".

Then, restart your computer and Windows 7 will reinstall all controllers automatically." Let us know what works, or what does not. Hope this helps, good luck.