When I plugged in the USB of the Simpledrive 2 TB drive, the power light goes on but my computers do not recognize it in "my computer". I have rebooted two computers and reconnect without any help. I'm slightly worried I have lost everything. Please help.

take the unit apart and physically check the connection , that USB is not only its interface but its power as well

If you have a SimpleTech SimpleDrive connected to your computer and you're experiencing problems with the external hard drive, there may be several reasons why it's malfunctioning. Troubleshooting your computer can help rule out common problems and the possibility that the hard drive may be defective. If you recently purchased the device and suspect there is something wrong with it, return the defective drive to SimpleTech or the reseller for a replacement. Incompatible USB Port Problems SimpleTech SimpleDrive plug and play options makes it easy for you to connect the device to your computer. But you may encounter problems if your computer's USB (Universal Serial Bus) ports are not compatible with the external hard drive. Make sure your ports are powerful enough to operate the drive. USB 2.0 ports are recommended, but if you're using an older computer with 1.0 ports, the hard drive will function much slower or you may receive an error message that the device is not compatible with your system. b> Missing External Drive Letter If you're unable to find the SimpleTech external hard drive's letter on your desktop after you have installed the drivers for the device, it's possible that the external drive may be assigned to another drive. Sometimes, the hard drive is assigned to a network drive and you may need to manually change the drive's letter in Disk Management. b> SimpleTech SimpleDrive Incorrectly Formatted b> SimpleTech SimpleDrive is normally pre-formatted for Windows NTFS (New Technology File System), but Mac users may need to copy the backup software and reformat the external hard drive for FAT32 or Mac OS to be able to use the external drive. If the external hard drive is not formatted correctly for your system, it may not function or work properly. b> External Hard Drive Inaccessible If you receive an error message that says "Drive Inaccessible," the SimpleTech SimpleDrive may not be able to read the service area of the platter. If the external hard drive emits a loud or abnormal sound, this could mean the device is failing.
Test the drive on another computer to see if it is working properly. Otherwise, the external hard drive's surface area may be damaged or corrupted.
Replacing a Defective Hard Drive You can return a defective hard drive that is under warranty to SimpleTech. The manufacturer will exchange the device if the seal is not broken. But if you break or tear the seal on the case, any warranty claims will not be accepted and the device will be returned back to you. SimpleTech will only accept the device if you contracted a commercial data recovery company to retrieve critical data from the external hard drive and the seal needed to be broken. Before returning the defective drive, you will need to secure a RMA (Return Merchandise Authorization) approval number from SimpleTech and furnish any invoices or documentation regarding the data recovery company's services
or if its a usb external drive you might need a usb 3 card installed on your computer your computer might not have enough usb output power USB 3 card will provide more power when needed to the device to gain maximum throughput and conserve power when the device is connected but is idling http://blog.premiumusb.com/2010/09/usb-2-0-vs-usb-3-0/ these can be purchased on Ebay cheap and easy to install http://www.ebay.com.au/itm/PCI-e-PCI-Express-USB3-0-Card-new-NEC-720200AF1-chipset-/330608109325?pt=LH_DefaultDomain_0&hash=item4cf9c7670d for roughly $9 or $10free postage Hope this helps.

the beeps are post during post the very first work is done by the ram all the memory in the ram is first transferred to the hard disk and remains active until turned off.
make sure that your RAM is securely seated,
click start control panel administrive tools computer management device manager scroll down universal serial bus controllers you should see a yellow question mark?
right click to reinstall drivers
when you plugged the external disk drive you got that windows could recognize the USB device change the cable just replace the cable of the hard disk everything should work fine again, sometimes the wires inside the cable will be damaged due to bending or stretching or placing heavy equipment upon the cable,
check the USB leads that attach to the motherboard usually red-white-green-black make sure they are securely seated and have no dust build up on them dust will cause static and a lot of unforeseen problems
hope this helps

Try another cable or try it on another computer. If you need more help, please call HitachiGST Tech Support M-F 8AM to 6PM PST at 1.888.426.5214 and a technician will be happy to help you.

Download testdisk and run it to see if it recognised in the list. If so use the intel option to find a boot sector

Check to see if its still under warranty. Most times they have at least 1 to 2 years. If it isn't, I would remove the drive from the case and slave it to your system to see if will work that way. Doing that will narrow it down if its a drive issue or a USB issue. Good Luck.

Change the orientation of the drive. i.e. if you had it standing vertical lay in flat. It worked for me. Hope this helps.

try plugging your HD into another desktop/laptop to see if your HD is functioning well on a different computer. Could be the USB cable problem. 

usb drive get faulty. replace it.

Hello

Have a look at the link below, it should be of help.

Click HERE to navigate.

Please feel free to let me know of you have any further questions.

Kind regards
Lock123