Use FileTouch utility to change file dates and times.

Windows keeps track of the date and time every file was created, and of the date and time it was last modified or opened, but it does not provide any ways that allow allows you to change these file dates and times. FileTouch is a command line utility that allows you to change them. It is similar to the well-known UNIX touch command.

DownloadDownload FileTouch.exe (16 KB).

Here is the help screen containing complete description and examples

Usage: FileTouch [/?] [/W] [/A] [/C] [/S] [/D date] [/T time] filemask

Command line parameters:

/? Print this help.
/W Change file modification date (Write date). This is the default.
/A Change file last access date (Access date).
/C Change file creation date (Create date).
/S Touch subfolders. By default only files are touched.
/D New file date. This switch must be followed by a date in mm-dd-yyyy format. If /D switch is not specified the current system date is used.
/T New file time. This switch must be followed by a time in hh:mm:ss 24-hour time format. If /T switch is not specified the current system time is used.
filemask The file mask to be used for the file search. Example: *.txt.

Run FileTouch.exe without parameters from the DOS command prompt to see full description of the supported parameters. Multiple "change" switches can be used with  a single FileTouch command. For example, FileTouch /W /A /C *.txt will change all 3 dates for all found text files.