Search the registry

Windows 7's REG, version 6.1, has a /F (Find) switch for the Query command that allows us to specify a pattern instead of an exact value to look for.

The command REG Query /? will display the following help:

REG Query KeyName [/v [ValueName] | /ve] [/s]
          [/f Data [/k] [/d] [/c] [/e]] [/t Type] [/z] [/se Separator]

  KeyName  [\\Machine\]FullKey
           Machine - Name of remote machine, omitting defaults to the
                     current machine. Only HKLM and HKU are available on
                     remote machines
           FullKey - in the form of ROOTKEY\SubKey name
                ROOTKEY - [ HKLM | HKCU | HKCR | HKU | HKCC ]
                SubKey  - The full name of a registry key under the
                          selected ROOTKEY

  /v       Queries for a specific registry key values.
           If omitted, all values for the key are queried.

           Argument to this switch can be optional only when specified
           along with /f switch. This specifies to search in valuenames only.

  /ve      Queries for the default value or empty value name (Default).

  /s       Queries all subkeys and values recursively (like dir /s).

  /se      Specifies the separator (length of 1 character only) in
           data string for REG_MULTI_SZ. Defaults to "\0" as the separator.

  /f       Specifies the data or pattern to search for.
           Use double quotes if a string contains spaces. Default is "*".

  /k       Specifies to search in key names only.

  /d       Specifies the search in data only.

  /c       Specifies that the search is case sensitive.
           The default search is case insensitive.

  /e       Specifies to return only exact matches.
           By default all the matches are returned.

  /t       Specifies registry value data type.
           Valid types are:
             REG_SZ, REG_MULTI_SZ, REG_EXPAND_SZ,
             REG_DWORD, REG_QWORD, REG_BINARY, REG_NONE
           Defaults to all types.

  /z       Verbose: Shows the numeric equivalent for the type of the valuename.

Examples:

  REG Query HKLM\Software\Microsoft\ResKit /v Version
    Displays the value of the registry value Version

  REG Query \\ABC\HKLM\Software\Microsoft\ResKit\Nt\Setup /s
    Displays all subkeys and values under the registry key Setup
    on remote machine ABC

  REG Query HKLM\Software\Microsoft\ResKit\Nt\Setup /se #
    Displays all the subkeys and values with "#" as the seperator
    for all valuenames whose type is REG_MULTI_SZ.

  REG Query HKLM /f SYSTEM /t REG_SZ /c /e
    Displays Key, Value and Data with case sensitive and exact
    occurrences of "SYSTEM" under HKLM root for the data type REG_SZ

  REG Query HKCU /f 0F /d /t REG_BINARY
    Displays Key, Value and Data for the occurrences of "0F" in data 
    under HKCU root for the data type REG_BINARY

  REG Query HKLM\SOFTWARE /ve 
    Displays Value and Data for the empty value (Default)
    under HKLM\SOFTWARE

As you probably know, searching the registry can be very time consuming.
Using the correct switches may save us a lot of time.

To search part of the registry, use the following syntax:

REG Query HKxx\subkey [/D|/K|/V] /F "search_pattern" /S [/E] [/C]

To search an entire registry hive, just omit the subkey:

REG Query HKxx [/D|/K|/V] /F "search_pattern" /S [/E] [/C]

Use /D to search the data (i.e. the registry values' values), /K to search for matching key names, /V to search for matching value names, or none of these switches to search keys, values and data.
Searches with /K or /V are fast, searches with /D or none of these switches are slow.
So make sure to use /K or /V if you do not need to search the registry data.

Use /C for cases sensitive searches, and /E for exact matches only (no partial matches).
My guess is that using /E and /C would make searches a fraction faster, especially when searching registry data.

To search remote registries, use:

REG Query \\remote_pc\HKxx\subkey [/D|/K|/V] /F "search_pattern" /S [/E] [/C]

Some examples:

Search for the string "C:\Program Files (x86)\ATI" in "HKEY_LOCAL_MACHINE\Software", no exact match (i.e. partial matches are allowed), case insensitive, search in keys, values and data:

REG Query HKLM\Software /F "C:\Program Files (x86)\ATI" /S

On my computer this search takes about 61 seconds.

Search for all values named "AppPath" in "HKEY_LOCAL_MACHINE\Software", exact matches only (e.g. RestoreAppPath is not a valid match), case insensitive:

On my computer this search takes about 7.5 seconds.

The same registry tree was searched, yet the difference in time is striking.
Searching for keys (/K) is even faster! Search for keys named "9.0":

REG Query HKLM\Software /K /F 9.0 /S /E

On my computer this search only takes 6 seconds.

My first batch file to take advantage of this technique is GetUninstall.bat.
It searches the registry for uninstall commands and displays only the ones whose name matches the specified search string.