Tracking down any changes you made to the registry using Tweak UI or Group Policy etc

One common registry scenario is to make a change to Windows XP using a tool such as the Group Policy Editor or Tweak UI, and then try to find which registry setting (if any) was affected by the change. However, because of the sheer size of the registry, this is usually a needle-in-a-haystack exercise that ends in frustration. One way around this is to export some or all of the registry before making the change and then export the same key or keys after making the change. You can then use the FC (file compare) utility at the command prompt to find out where the two files differ. Here’s the FC syntax to use for this:

FC /U pre_edit.reg post-edit.reg > reg_changes.txt

Here, change pre_edit.reg to the name of the registration file you exported before editing the registry; change post_edit.reg to the name of the registration file you exported after editing the registry; and change reg_changes.txt to the name of a text file to which the FC output is redirected. Note that the /U switch is required because registration files use the Unicode character set.