How to change file extensions via command promopt

STEPS  1: -

1.GO TO THE FOLDER WHERE VIDEO's 

ARE PLACED

(LIKE HERE OUR ALL VIDEO ARE

 PLACED IN "E" DERIVE)

GO TO "E" DERIVE

change extension

STEPS  2: -

OPEN CMD

GO TO THE "E" DERIVE

BY CHANGING DIRECTORY 

"C" TO "E"

BY TYPING 'E:' AND HIT ENTER AGAIN

cmd

COPY THE ADDRESS OF THAT

FOLDER WHERE THE VIDEOS ARE PLACED

change extension

current extension is .mp4

STEPS  3: -

TYPE CD AND

PASTE THE ADDRESS IN CMD (command prompt)

AND PRESS HIT ENTER

AFTER THAT

STEPS  4: -

 TYPE

"ren (space)*.mp4(current extension  ) *.avi(new extension)"(this must be typed without quotation marks)

and hit enter

STEPS  5: -

congratulations your file extension has been changed

lets check it

------------------------QUICK TIPS----------------------

1. Open cmd.
2. Copy the folder addres where the videos are placed.
3. Paste the address in cmd and type "ren (space)*.mp4(current extension  ) *.avi(new extension)"(this must be typed without quotation marks).
4. And hit enter.