I tried placing an order but it's getting rejected everytime. Why is it so? And how to check availabe fund in my trading account?

Pl specify the segment in which you are unable to place order and during what time of the day.

To check the available fund just click limits tab and select equity option and click submit.

Depends on a lot of factors.

First check balance using Ctrl+1

If you are placing after market order use Ctrl + F1 for buy, Ctrl + F2 for sell.

During markets F1 for Buy and F2 for sell.

Above instructions and shortcut keys are for the desktop trading app

both BSE & NSE ,this is what i get ," RMS:Blocked for bse_cm NRML broker- ZERODHA block type: ALL" for rejection…plz hlp!

At what time are you placing this order? Is it within trading hours?
Did you check your balance?