There are two parts to the issue.

1.  You will need to contact Dell support by voice to have them issue a master password to remove the CMOS portion of the password lock.  They will insist on verification of ownership before assistance is rendered.  There is also a charge for the call unless the system is in your name and under warranty.

2.  This WILL NOT remove the password from the drive.  Once the CMOS is cleared, if your plan is to reload the OS, simply replace the drive.  It's the cheaper option.

If you need the data on the drive, you'll need to send it to a recovery specialist that can remove the password from the drive itself.

DO NOT install another drive until the CMOS is cleared -- or it will inherit the password when you power the system on.

I am having the exact same issue as above.

Based on your response, I have questions...

Dell is really big on re-selling refurbished PC's through budget computer/surplus stores.
I got my OptiPlex 380 from Forest City Surplus in London, ON.

Zero information or documentation is given regarding warranties or registering the product.

It's safe to assume that there would be no verification of ownership for refurbished products purchased through a third party. How then is it even remotely fair to be denied or charged for assistance for a problem that is beyond the customer's control?

This leads to another question:
Who puts the password on the hard disk to begin with?
I know I certainly didn't and I've used my system for several months without issue, until today.

If it's Dell, why is the password not passed along to the customer, directly or through 3rd party sellers?

The purpose of a hard drive password is to prevent access to the data on the drive other than to the owner.

As for used systems, they're being sold though third parties - just as you can buy a used Rolls Royce through a used car dealer doesn't mean it's supported by the manufacturer when it's sold that way.

Dell has a standing policy of supporting security measures ONLY to registered end users.  

If you're saying you did not set the password on the drive, then one of two things happened:  the drive has failed or the mainboard has.  One way or another, if you can't verify your ownership with Dell, you'll need to replace BOTH the drive and the mainboard.

Thanks for the reply.

I have completed a Transfer of Ownership and am waiting for that to be completed on DELL's end.
I am also currently receiving email support for this issue.

I was able to run diagnostics from BIOS and am currently using the system via a flash drive OS,
so I'm confident that I do not have issues with the mainboard. If I have to accept the loss of the hard drive, then there's not much I can do. Most of my data was backed up, but not everything - so there is still a loss.

I am concerned, however, when you post this:
"DO NOT install another drive until the CMOS is cleared -- or it will inherit the password when you power the system on."

The BIOS password must be cleared.

A brand new never used hard drive will be passworded and rendered dead until this is cleared.

CMOS DOES NOT STORE The password.

Clearing CMOS DOES NOT clear the password.

Everyone is incorrect here. No worries, there is confusion, typical online, especially quick glance at threads people miss important details.

To quickly address the OP, his computer only has a hard drive password set per the picture. Hard drive passwords take priority first before other passwords if set. SO if you simply disconnect the hard drive, the system will POST and you will be able to then enter the CMOS/BIOS as long as a password has not been additionally set for the system. Further more, putting a new hard drive that obviously has no password will work just fine. Just as others correctly pointed out the hard drive password is only on the hard drive. SO a new hard drive will not become "infected". Now it is possible that there could be additional passwords but you first have to get pass the hard drive password to see that prompt. I am guessing not as the OP said he can boot from a external drive (clue).

To clear a CMOS/BIOS/SYSTEM password, normally you just have to remove the CMOS battery or jump a pair of pins to clear that.

To recap, people got side tracked because the OP said he tried to get to the CMOS/BIOS/SYSTEM but gets the password screen (note it specifically says hard drive password). That is normal behavior as the hard drive password appears first, before entering the system. I know it sounds counter intuitive but this is just how it works.

Bottom line somebody recently set the password. AKA a text book laying on top of the keyboard during boot.. bad luck.

It is this post that's not correct.  If there is a CMOS hard drive password on the system and you put in a new drive, the replacement drive WILL inherit that password, rendering it locked.

The jumpers on a desktop mainboard WILL clear the master CMOS password but will NOT clear a hard drive password.

I have installed another hard drive but it is working fine means no password.

How can I break the password of my old hard drive, I have lots of data

Hard Disk password protected (recovery disk)

i have same problem  do you know what i have to do next