Windows XP Problem (PLEASE help)

My sister got a Dell computer for college last year...she\'s home for the summer, so the family\'s using it.  I got on today...and it\'s not working.  It\'s got a windows XP OS...but when I turn the computer on and click on any of the screen names, I get three different messages...

Windows Product Activation

This copy of Windows must be activated w/ Microsoft before you can logon.  Do you want to activate windows now.  

I click \'yes\'

Windows cannot load the user profile you have selected but has logged you on with the system\'s default profile.
DETAIL:  Insufficient system resources exist to complete the requested service.

Then I get a different message altogether, but I\'m assuming they\'re connected...

A problem is preventing Windows from accurately checking the license for this computer.
Error Code: 0x800705aa

It was working fine last night...so I just don\'t know what could be wrong.  

Thanks for any help

-Ethan

microsoft\'s support page

SYMPTOMS
When you start Microsoft Windows XP, you may receive the following error message:

A problem is preventing Windows from accurately checking the license for this computer. Error code: 0x80070002.
CAUSE
This issue can occur if one of the following conditions is true:
The default security provider in Windows XP has been changed.
The system drive letter has changed.
The security provider issue has been reported with Dell computers on which the Dell Assistant software is installed.

NOTE: This issue can be caused by any software that changes the default security provider. It is not limited to Dell computers or the Dell Assistant software.

WORKAROUND
Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To work around this issue, use the appropriate method.
Reset the Default Security Provider in Windows XP
To reset the default security provider in Windows XP, delete the relevant keys in the Windows registry. To do this:
Start the computer. Press the F8 key during startup to start the computer in Safe mode.
Start Registry Editor (Regedt32.exe).
Delete the following keys in the Windows registry:
HKEY_USERS\\.DEFAULT\\Software\\Microsoft\\Cryptography\\Providers
HKEY_USERS\\S-1-5-20\\Software\\Microsoft\\Cryptography\\Providers

Quit Registry Editor.
Restart the computer.
Reset the Drive Letter of the System Drive
To reset the drive letter of the system drive, use one of the following methods.
Undo the action that changed the drive letter of the system drive.
If you can run Registry Editor, update the drive letter for the system drive in the Windows Registry. To do this:
Start Registry Editor.
Open the following key in the Windows registry:
HKLM\\Software\\Microsoft\\Cryptography\\Defaults\\Provider

In each key under the Provider key, change the drive letter in the ImagePath value setting to match the new drive letter for the system drive.
Quit Registry Editor.
Restart the computer.

STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

Got the Dell assitant installed?  Try the workaround...  but remember, edit the registry at your own risk.