Why did Vista lose my user profile?

Question

My computer crashed last night and, upon rebooting and scanning the disk, it proceeded to load a default Vista user profile.

The desktop now shows default icons and background, the start menu is back to default, and the shortcuts to Documents, Music, and Pictures are all empty.

When I go to C:/Users/MyUsername, all of my data is right there! Why isn't Vista loading my profile given that the data is still exactly where it's supposed to be?

How can I fix this?

---UPDATE---

Given that a reboot hasn't fixed the problem, it does seem that a more involved process is necessary. Clarifying question:

1. The username I used when my computer crashed is SSCirrus. I am currently logged in as SSCirrus (my desktop looks new and has only the icons that appear on every profile). Does it solve my problem to copy everything from the full C:/Users/SSCirrus to the blank 'SSCirrus' folder that I see on my Start Menu?
2. @hello71: Apologies for the newbie question - what kind of effect does losing the HKCU registry settings have?

Answer 1

It could be that your profile got corrupted. If that is the case you can ether reformat and reinstall or create a new profile and migrate your data to that profile by following these steps....

Log on as a user other than the new user you just created or the user that you want to copy files from.

Open Documents by clicking the Start button Picture of the Start button, and then clicking Documents.

Click the Tools menu, and then click Folder Options.

If you don't see the Tools menu, press ALT.

Click the View tab, click Show hidden files and folders, clear the Hide protected operating system files check box, and then click OK.

Locate the C:\Users\Old_Username folder, where C is the drive that Windows is installed, and Old_Username is the name of the profile you want to copy files from.

Select all of the files and folders in this folder, except the following files:

Ntuser.dat

Ntuser.dat.log

Ntuser.ini

Click the Edit menu, and then click Copy.

If you don't see the Edit menu, press ALT.

Locate the C:\Users\New_Username folder, where C is the drive that Windows is installed, and New_Username is the name of the new user profile you created.

Click the Edit menu, and then click Paste.

If you don't see the Edit menu, press ALT.

Log off, and then log back on as the new user.

If you have e-mail messages in an e-mail program, such as Windows Mail, you must import your e-mail messages and addresses to the new user profile before you delete the old profile. If everything is working properly, you can delete the old profile.

Answer 2

I deal with this all the time. This is a good article I use to get back a users corrput profile:

http://www.vistax64.com/tutorials/135858-user-profile-error-logged-temporary-profile.html

You can also rename the profile C:\Users\MyNameHere\ to C:\Users\MyNameHere.old, reboot the computer, login and then copy all of the info you can from the .old profile to the new one. You might not get everything back, but I am sure the most imprtant information would be taken care of!!