Remove "out=wfn" and the line containing .wfn file name and retry.
There is no reason to export .wfn file, since Multiwfn fully supports .fch file, which can be converted from .chk file by formchk.

but sir see when pop=(full,nbo) is there, then normal termination of job occurs, although this is wrong method to find out wbi(wiberg bond indices) cal.

plz reply sir

sir when i put pop=nboread , then i got the following error

You need to use "nboread" instead of "nbo", otherwise the information of $NBO section will not be read by Gaussian.

sir, input file although contains the keyword 'DMNAO', but till i am not able to do wbi bond order analysis.