Restoring a registry file

If a registry file has been accidentally deleted or corrupted, what is the procedure for restoring it? Can a registry file from a networked computer be copied to another workstation?
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whoamiConnect With a Mentor Commented:
OK someone_whoknows,

First boot your computer to safe mode command prompt only
to do this press F8 while the computer is booting and choose safe mode command prompt only
In the C:\windows directory type:  Attrib -r -h -s system.dat
then change to the root directory C: and type :  Attrib -r -h -s system.1st
Copy SYSTEM.1ST to the C:\windows directory
Then in the C:\windows directory rename SYSTEM.1ST to SYSTEM.DAT
Boot your computer in safe mode , same way but choose  Safe Mode
Then click start and Run  Type in regedit and export the registry file
Then reboot your computer to Safe Mode command prompt only
Rename SYSTEM.SWK to SYSTEM.DAT and reboot in Safe Mode
Then run regedit again and import the registry file

This will overwrite any corrupt files and still keep any hardware setup that you have added.

You can select a Key in registry and export it. This creates a .reg file that you can then import to another registry. I often do this before upgrading software in case I run into problems but don't want the entire registry.
look for system.da0 and user.da0 these are backup's. If they are there rename them to system.dat and user.dat. If your registry is just corrupt email me at and I will tell you have to fix that.
Lee W, MVPTechnology and Business Process AdvisorCommented:
system.da0 and user.da0 are backups from the last time the system was booted.  Additionally, 95 setup sometimes creates a file called system.1st.  This is usually located in the root directory of the c: drive and if you have this and restore it, you'll be reset back to when Win95 was first setup - with all the original hardware it detected.  If you changed a lot of hardware (modems, motherboard, soundcard, etc.) you probably shouldn't use this as it will be out of date.  (All these files will probably be hidden).

What I'd recommend doing is periodically copying the user.dat and system.dat to different locations as backup.  I'd do this whenever you add new software or hardware (if you're prone to registry problems).  You could even write a small batch program to do this for you.
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