Exchange backup completing partially

Look at the error in Details tab of the status 1 job.
It will tell you the exact reason for the error.
This will be an error message from Exchange, not NBU.

This means that only your Exchange admin can answer your question and give you a reason/explanation.

I checked the job details and got the information about file which did not backup, but when i took login of exchange server and tried to find that file  i didn't get such file which was showing in backup job details .

Please Advice .

Thank You !!
 

That is why you need to talk to Exchange Admin. 

If Backup Policy only lists Information Stores and Job Details error is not specifically mentioning an Information Store that is explicitly mentioned in the policy Backup Selection, then it means that Exchange somehow believes that something must be backed up that is no longer there.

We cannot help further without any details from your side, such as error in Details and contents of Backup Selection. All of this will help us to confirm that this is not NBU issue.
You need to sort this out with Exchange Admin.

10/16/2014 6:09:23 PM - Info nbjm(pid=8160) starting backup job (jobid=806404) for client MBX01, policy MAIL_EXCH_DAG01_PRD_ExecutiveDB1, schedule DAILY-FULL  
10/16/2014 6:09:24 PM - estimated 0 Kbytes needed
10/16/2014 6:09:24 PM - Info nbjm(pid=8160) started backup (backupid=dag01_1413468563) job for client HO-MBX01, policy MAIL_EXCH_DAG01_PRD_ExecutiveDB1, schedule DAILY-FULL on storage unit medho2_ho_stu1
10/16/2014 6:09:25 PM - started process bpbrm (8488)
10/16/2014 6:09:34 PM - Info bpbrm(pid=8488) -HO-MBX01 is the host to backup data from     
10/16/2014 6:09:34 PM - Info bpbrm(pid=8488) reading file list from client        
10/16/2014 6:09:42 PM - connecting
10/16/2014 6:09:45 PM - Info bpbrm(pid=8488) starting bpbkar32 on client         
10/16/2014 6:09:45 PM - connected; connect time: 00:00:03
10/16/2014 6:10:49 PM - Info bpbkar32(pid=17848) Backup started           
10/16/2014 6:10:50 PM - Info bptm(pid=6624) start            
10/16/2014 6:10:50 PM - Info bptm(pid=6624) using 524288 data buffer size        
10/16/2014 6:10:50 PM - Info bptm(pid=6624) setting receive network buffer to 2098176 bytes      
10/16/2014 6:10:50 PM - Info bptm(pid=6624) using 512 data buffers         
10/16/2014 6:10:54 PM - Info bptm(pid=6624) start backup           
10/16/2014 6:10:55 PM - Info bpbkar32(pid=17848) INF - waiting for mount mutex       
10/16/2014 6:10:57 PM - Info bptm(pid=6624) backup child process is pid 8256.2004       
10/16/2014 6:10:57 PM - Info bptm(pid=8256) start            
10/16/2014 6:10:57 PM - begin writing
10/16/2014 9:43:25 PM - Info bpbrm(pid=8488) DB_BACKUP_STATUS is 0          
10/16/2014 9:43:26 PM - Info bpbkar32(pid=17848) 5000 entries sent to bpdbm        
10/16/2014 9:43:27 PM - Info bpbkar32(pid=17848) 10000 entries sent to bpdbm        
10/16/2014 9:43:27 PM - Info bpbkar32(pid=17848) 15000 entries sent to bpdbm        
10/16/2014 9:43:28 PM - Info bpbkar32(pid=17848) 20000 entries sent to bpdbm        
10/16/2014 9:43:29 PM - Info bpbkar32(pid=17848) 25000 entries sent to bpdbm        
10/16/2014 9:43:30 PM - Info bpbkar32(pid=17848) 30000 entries sent to bpdbm        
10/16/2014 9:43:30 PM - Info bpbkar32(pid=17848) 35000 entries sent to bpdbm        
10/16/2014 9:43:31 PM - Info bpbkar32(pid=17848) 40000 entries sent to bpdbm        
10/16/2014 9:43:32 PM - Info bpbkar32(pid=17848) 45000 entries sent to bpdbm        
10/16/2014 9:43:33 PM - Info bpbkar32(pid=17848) 50000 entries sent to bpdbm        
10/16/2014 9:43:34 PM - Info bpbkar32(pid=17848) 55000 entries sent to bpdbm        
10/16/2014 9:43:34 PM - Info bpbkar32(pid=17848) 60000 entries sent to bpdbm        
10/16/2014 9:43:35 PM - Info bpbkar32(pid=17848) 65000 entries sent to bpdbm        
10/16/2014 9:43:36 PM - Info bpbkar32(pid=17848) 70000 entries sent to bpdbm        
10/16/2014 9:43:37 PM - Info bpbkar32(pid=17848) 75000 entries sent to bpdbm        
10/16/2014 9:43:38 PM - Info bpbkar32(pid=17848) 80000 entries sent to bpdbm        
10/16/2014 9:43:39 PM - Info bpbkar32(pid=17848) 85000 entries sent to bpdbm        
10/16/2014 9:43:40 PM - Info bpbkar32(pid=17848) 90000 entries sent to bpdbm        
10/16/2014 9:43:41 PM - Info bpbkar32(pid=17848) 95000 entries sent to bpdbm        
10/16/2014 9:43:49 PM - Info bpbrm(pid=8488) from client -dag01: TRV - Starting granular backup processing for (/Microsoft Exchange Database Availability Groups/unb-dag01.mas.unb.com\Microsoft Information Store:\ExecutiveDB1\). This may take a while...
10/16/2014 11:34:06 PM - Info bpbrm(pid=8488) from client unb-dag01: TRV - Granular processing failed!     
10/16/2014 11:34:06 PM - Error bpbrm(pid=8488) from client unb-dag01: ERR - Error encountered while attempting to get additional files for Microsoft Information Store:\ExecutiveDB1\Logs_1413466293\
10/16/2014 11:34:06 PM - Error bpbrm(pid=8488) from client unb-dag01: ERR - Exchange granular restore from this image may not work.
10/16/2014 11:34:06 PM - Info bpbrm(pid=8488) from client -dag01: TRV - Exchange granular database changes were backed up successfully.
10/16/2014 11:34:55 PM - Info bptm(pid=6624) waited for full buffer 127284 times, delayed 891249 times    
10/16/2014 11:34:56 PM - Info bptm(pid=6624) EXITING with status 0 <----------        
10/16/2014 11:34:56 PM - Info bpbrm(pid=8488) validating image for client dag01        
10/16/2014 11:34:58 PM - Error bpbrm(pid=8488) cannot send mail to    
10/16/2014 11:35:00 PM - end writing; write time: 05:24:03
the requested operation was partially successful(1)

The job was successfully completed, but some files may have been
busy or unaccessible. See the problems report or the client's logs for more details.