Regedit file format

Question

I would like to document the file format of regedit utility, so data can be merged into the registry.

From the command-line you can (silently) merge data from a batch file like this:

regedit /s file.reg

Exporting from a subkey goes like this:

regedit /e file.reg "HKEY_XX\key"

Answer 1

Remove keys and values by using the minus sign (-).

REGEDIT4
[-HKEY_CURRENT_USER\RemoveThisTree]
[HKEY_CURRENT_USER\RemoveValue]
"valueName"=-

References

• Minus sign to delete mentioned here: MSKB310516: How to add, modify, or delete registry subkeys and values by using a .reg file (Archived here.)

• Minus sign to delete, semicolon to comment and IF/ENDIF mentioned here: MSDN: Registry File (Compact 2013) (Archived here.)

Answer 2

Documenting the .reg file format is really more Microsoft's job.