Does anyone know How To calibrate Digital Multimeter?

It seems not giving the accurate resistance when shorting the probes together on resistance mode or even on continuity mode! It should read 000 digits as before it use to, not 002 or 3 or 4 which is kind of misleading, if you know what I mean.

Any help would be appreciated

Your meter is correct and does not need calibrating. How does your meter know what sort of leads you are using and how long they are. For normal use 0.00X ohms is not going to cause you an issue, get real if you are fixing and reading resistors they have a higher tolerance than that.

Well thanks for response, my leads R the same normal length as before was
However it use to read absolute zerrrrooooo. When I use to short them together!
But having said that I'll give it a go see what happen.

Thanks again.

1. Have you put in a fresh set of batteries in the meter?
2. Sometimes the banana plug "tangs" of the test leads compress and do not make a good connection inside the banana jack. Take a small pick or jewelers screwdriver and pry the tangs outward some.
3. Have you mistakenly tried measuring voltage when the meter was in the Resistance Mode?
4. What kind of meter is this? A high priced Fluke or a cheap Radio Shack?

In addition to the points annymous made try cleaning your probe tips with thin sandpaper there may be resistance building up.

It seems like he's ashamed to say what meter brand he's got.

If it was reading absolute zero before it must be a cheap meter as that reading is incorrect. The leads read more than .001 ohm and any movement whilst holding the probes would cause a reading. If you have a low ohms meter you would find that there is a correction to zero the leads an ordinary multimeter is not used for that function and has a tolerance of a certain percentage so read the instruction manual.