SQL Server Backup Job failed multiple times I am getting the same error as mentioned by Mr.Ali 

Sql Server Backup Job failed

Can anyone please explain the possible ways to fix this error as the backup is failing since 1 month.

Here is the Job history log

Executed as user: SAP\sqladmin.
Microsoft (R) SQL Server Execute Package Utility
Version 10.50.1600.1 for 64-bit
Copyright (C) Microsoft Corporation 2010. All rights reserved.
Started:  21:00:00
Progress: 2014-10-03 21:00:05.83
Source: {E7436186-D15A-4485-92B4-7623DA7DDF4D}
Executing query "DECLARE @Guid UNIQUEIDENTIFIER EXECUTE msdb..sp...".: 100% complete
End
Progress
Error: 2014-10-03 23:32:25.53
Code: 0xC002F210    
Source: Back Up Database Task Execute SQL Task
Description:
Executing the query "BACKUP DATABASE [P01] TO  DISK =N'\\cmgsap31.sap...."
failed with the following error:
"Write on "\\cmgsap31.sap.logica.com\p$\Central-MS-SQL-Backup\SAP0233_P01_Full.bkp"
failed: 64(failed to retrieve text for this error. Reason: 15105) 
BACKUP DATABASE is terminating abnormally.
10 percent processed.
20 percent processed.
30 percent processed.
40 percent processed.
50 percent processed.
60 percent processed.
70 percent processed.
80 percent processed.". 
Possible failure reasons: Problems with the query,
"ResultSet" property not set correctly, parameters not set correctly,
or connection not established correctly.
End Error 
DTExec: The package execution returned DTSER_FAILURE (1).
Started: 21:00:00
Finished: 23:32:25
Elapsed:  9145.29 seconds.
The package execution failed.  The step failed.
Well based on Reason:15105 I think that SQL Server doesn't have permission to access to the path you check the permissions of the account that is assigned to the SQL service account? or other reason would be that there is not enough free space to create backup.