I AM GUSESSING this happens when an other job either an full backup starts before completing of the previous log backup.....because even i got th same error...

Error: 18210, Severity: 16, State: 1.

BackupMedium::ReportIoError: write failure on backup device 'VDI_209FE1C2-2F07-46D7-B966-BB2E687AAB24_0'. Operating system error 1223(The operation was canceled by the user.).

Error: 3041, Severity: 16, State: 1.

BACKUP failed to complete the command BACKUP DATABASE Aris702P. Check the backup application log for detailed messages.

Error: 18210, Severity: 16, State: 1.

BackupVirtualDeviceFile::RequestDurableMedia: Flush failure on backup device 'VDI_209FE1C2-2F07-46D7-B966-BB2E687AAB24_0'. Operating system error 995(The I/O operation has been aborted because of either a thread exit or an application request.).

The alert for 'unsent log' has been raised. The current value of '97985' surpasses the threshold '20000'.

Error: 18456, Severity: 14, State: 11.