I have a ibm thinkpad that boots to a black screen with a little computerand lock icon in the upper left hand corner

SOURCE: I am a service provider

WHEN I TURN ON THE COMPUTER, THE IBM LOGO COMES UP BUT THEN THE SCREEN TURNS BLACK. THERE IS AN ERROR MSSG STATING 0271 AND THEN A PADLOCK SHOWS UP.

SOURCE: can't unlock my ibm thinkpad t23

Your computer has been protected by a Power On password.
If you didn't set this password then ask the person who set the password on the computer.
This password is near impossible to crack, try various names, pets, kid's names, family names/places, street names etc. There are no back door passwords and the password is not stored in the BIOS and removing the BIOS battery won't erase the password.
The password is stored on an EEPROM chip and you need electronic knowledge to build an EEPROM reader, then pull your laptop apart, solder the reader to your laptop, connect the reader's connector to a working computer, and run a program to read the contents of the EEPROM, identify the password from the downloaded data, unsolder the reader, put the laptop back together, boot up and insert the password. You can now enter the BIOS and change the password or remove it.
For further info goto http://sodoityourself.com

The Power On password and the Hard drive password are designed to prevent unauthorized access to the laptop and the data that is stored on its hard drive.
Removing the hard drive from the protected laptop and inserting it into another laptop will not work, you still cannot access the data on the hard drive without the correct password.

SOURCE: thinkpad r50

The Power On Password problem is near impossible to crack. It is designed to prevent unauthorized access to the Thinkpad and removing the BIOS battery will not remove the password because the password is stored on an EEPROM chip.
There are no backdoor passwords available, the only option is to ask the person who set the password.
OR
There is a way to hack into the Thinkpad to see and remove the password but it requires electronic skills, a program and a working computer.
For details on how to do this go to :-
http://sodoityourself.com/hacking-ibm-thinkpad-bios-password/

SOURCE: PC won't run: Fan Error

This is a self test that is checking the fan and finding that it is in error. You might have the fan damaged or else just stuck with dust inside and therefore to protect from over heating the laptop gives you this error.

Please check if the fan actually works when you switch on.

SOURCE: My IBM ThinkPad showing a black screen with a

That usually means there is a system password that needs to be entered. If you do not know it, you must remove the CMOS battery from the laptop and reset it.