Resetting and Reclaiming a Dell Latitude 5520 with BIOS Restrictions
This documentation provides a full guide to resetting a Dell Latitude 5520 when the system is locked with an admin account and BIOS password from a no-longer-existent company.
Goals
- Perform a full system wipe and install a fresh copy of Windows
- Remove old admin accounts and restrictions
- Bypass or reset BIOS password if necessary
1. Attempting a Clean Windows Installation
Standard Steps (Blocked in This Case)
- Create a bootable Windows USB using the Microsoft Media Creation Tool.
- Boot the laptop from USB via F12.
- Use the installer to delete all partitions and install a fresh copy of Windows.
Blocked: BIOS password prevents USB boot and boot order changes.
2. BIOS Password Lock
Symptoms
- Cannot access BIOS (F2 prompts for admin password)
- Cannot boot from USB (F12 is restricted)
- Cannot change boot options
Why You Cannot Fix It in the Registry
- BIOS password is stored in non-volatile memory, not in the Windows registry.
- Registry edits cannot affect firmware-level controls.
3. Bypassing BIOS Password
Option 1: Clear CMOS Battery (Low Success Rate)
- Open the back panel.
- Locate the CMOS (RTC) battery — small round battery with a cable, often labeled RTC_BAT or BAT.
- Disconnect the cable.
- Press and hold power button for 30-60 seconds.
- Reconnect and boot.
Option 2: Contact Dell
- Provide proof of ownership (service tag, company documents, etc.)
- Dell may issue a master password or instructions.
Option 3: Replace Motherboard
- Replaces the NVRAM storing the password.
- Most reliable (but expensive) option.
4. Offline Password Reset Tool (Once BIOS Access is Restored)
Using Offline NT Password & Registry Editor
- Download the ISO from http://pogostick.net/~pnh/ntpasswd/ (opens in a new tab)
- Use Rufus to create a bootable USB with the ISO.
- Boot from USB (once BIOS access is restored).
- Follow prompts to select Windows partition and user account.
- Choose to clear the password or delete the account.
- Save changes and reboot.
Note: This only works for local accounts and cannot bypass BitLocker.
5. Intune or Registry Reset
- Cannot enroll a device in Intune or reset through it without local admin access.
- Registry edits cannot remove locked admin accounts or affect BIOS.
6. USB That Forces a Reset on Boot?
No, modern laptops (especially business models) block any auto-executing USB behavior without manual user input or BIOS permission.
Even auto-install USBs require manual boot access.
Conclusion
To reclaim a locked Dell Latitude 5520, you must first bypass the BIOS password. Afterward, you can boot from USB, reset Windows, and remove any previous user restrictions.