Windows 7 - Slow computer and vanishing hard drive

Hi Guys,
I went out a bought a Roku adapter in order to view movies from Net Fliks. Due to the result of adding this piece of hardware my E drive vanished and my computers speed dropped appreciably. I took my PC to an expert and the "missing drive" appeared but when I re-hooked it up at home my drive once again did not appear. Just a warning that if you experience a very slow pc or missing drives check for external hardware items ie Roku.

if you fill out the specs of your computer in the bottom left hand corner of your post, as well as the model of your Roku adapter it will help a lot.

My computer is a custom made unit but the following is the system information;
System Information report written at: 11/17/11 08:19:05
System Name: OWNER-PC
[System Summary]

Item Value
OS Name Microsoft Windows 7 Ultimate
Version 6.1.7601 Service Pack 1 Build 7601
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Name OWNER-PC
System Manufacturer System manufacturer
System Model System Product Name
System Type x64-based PC
Processor Intel(R) Core(TM) i5 CPU 650 @ 3.20GHz, 3201 Mhz, 2 Core(s), 4 Logical Processor(s)
BIOS Version/Date American Megatrends Inc. 0401, 12/2/2009
SMBIOS Version 2.6
Windows Directory C:\Windows
System Directory C:\Windows\system32
Boot Device \Device\HarddiskVolume1
Locale United States
Hardware Abstraction Layer Version = "6.1.7601.17514"
User Name owner-PC\owner
Time Zone Eastern Standard Time
Installed Physical Memory (RAM) 4.00 GB
Total Physical Memory 3.84 GB
Available Physical Memory 2.01 GB
Total Virtual Memory 7.68 GB
Available Virtual Memory 5.66 GB
Page File Space 3.84 GB
Page File C:\pagefile.sys
The Roku is an XD Model number 2050x