/d The data to assign to the registry ValueName being added. /f Force overwriting the existing registry entry without prompt. ...

/d       The data to assign to the registry ValueName being added.

  /f       Force overwriting the existing registry entry without prompt.

  /reg:32  Specifies the key should be accessed using the 32-bit registry view.

  /reg:64  Specifies the key should be accessed using the 64-bit registry view.

Examples:

  REG ADD \\ABC\HKLM\Software\MyCo
    Adds a key HKLM\Software\MyCo on remote machine ABC

  REG ADD HKLM\Software\MyCo /v Data /t REG_BINARY /d fe340ead
    Adds a value (name: Data, type: REG_BINARY, data: fe340ead)

  REG ADD HKLM\Software\MyCo /v MRU /t REG_MULTI_SZ /d fax\0mail
    Adds a value (name: MRU, type: REG_MULTI_SZ, data: fax\0mail\0\0)

  REG ADD HKLM\Software\MyCo /v Path /t REG_EXPAND_SZ /d ^%systemroot^%
    Adds a value (name: Path, type: REG_EXPAND_SZ, data: %systemroot%)
    Notice:  Use the caret symbol ( ^ ) inside the expand string