USB Won't Attach or Else Can't Write

[USBDepression]

I hate to start a new thread on this topic, but I have tried everything anyone has suggested anywhere online.
Sometimes I feel like I have the worst luck. Like others, I can't seem to see my USB on my guest. Some facts:
1. I am running Windows 8.1 (64bit) on both my host and guest.
2. I am running VB 4.3.30 and I have downloaded the extension 4.3.28
3. I have checked the "Enable USB 2.0 (EHCI) Controller" in settings.
4. I have created "New Filter 1" and "My USB Name" Filter in every combination (In fact, I now show four identical copies to choose from when I add a "My USB Name" Filter. Does anyone know how to delete these? It is so confusing...).
5. I have edited the "My USB Name" filter and blanked out everything but its name.
6. I have put my USB in the 3.0 slot and the 2.0 slot on my computer.

But I still get one of these two messages every time:
1. "The Instruction at 0x----------- referenced memory at 0x--------. The memory could not be written. Click okay to terminate the program." Clicking okay shut down the guest.
NOTE: I get this automatically when I boot the VM if the USB is in the slot and I have chosen the wrong (or right?) filter. My host computer chimes to tell me that the USB has been unplugged, so I am guessing that the guest is recognizing it and trying to read it. It will also give me this message if I choose the wrong filter from "devices" inside the VM.

2. "Failed to Attach the USB device . . . busy with a previous request. Please try again later."
NOTE: I get this message if I click on ANY of the USB filters from inside the VM, whether they are attached or not. Sometimes I get this message if I have plugged the USB device in.

Any ideas?

[USBDepression]

I have been moving it around from slot to slot and it has just given me this message:
"Failed to attach the USB device ---- to the virtual machine -----. Failed to create a proxy device for the USB device. (Error: VERR_IO_GEN_FAILURE_)."

Hey, if it is something new, I figure it is something to work with.

[USBDepression]

Okay. I have tried three different brands. Here is how it works: Even if I haven't made a filter for the new drive it immediately terminates the program as soon as I plug the drive in. Regardless of filters. Regardless of anything really.