Question : Problem: Unexpectedly running out of C:drive space!

Computer:
- HP Pavilion dv8000t laptop, recently purchased
- WinXP Pro, SP2
- 100GB HDD

Background:
- HDD partitioned into 90 GB C:drive and 10GB D:drive (recovery disk)
- C:drive stats:
      - total capacity:      82.85 GB
      - Used:            70.92
      - Free:            11.93
- D:drive stats:
      - total capacity:      9.27GB
      - Used:            8.11
      - Free:            1.16

Actions taken:
- Cleaned up drive (chkdsk)
- defragmented drive
- turned off System Restore to remove historic restore points, then turned it back on
- folder options:
      - "Show Hidden Files & Folders" YES
      - "Show Protected Op Sys Files…" YES

Result on C:drive:
- The expected culprits in the root add to only 32.9GB; these include:
      - Docments and Settings folder
      - Program Files folder
      - Windows folder
- Hidden System Files added to 38.1 GB:
      - USMT.TMP      33.9 GB
      - hiberfil.sys      2.1
      - pagefile.sys      2.1

Question:
- In order to free up space on C:drive, what can I do about these hidden files…especially USMT.TMP?  Can I get rid of?

Answer : Problem: Unexpectedly running out of C:drive space!

The USMT.TMP is the User Settings Migration Tool (the file which the files and settings transfer wizard creates when you copy user info from an old computer to a new one).
Once this has been carried out successfully and you are happy that all is ok, you can delete it.

hiberfil.sys is the file that is created (the size of your installed RAM) for when your system goes into hibernation.
If you never use hibernation, then turn it off and on reboot the file should be gone. (To turn it off, right click desktop, >properties>screen saver>power>hibernate - then uncheck the box and apply).

pagefile.sys is your swap file (a part of your hard drive that is used as virtual memory). Leave intact as windows manages what is required here.