Failing backups error EC8F1C50, E7D10017, E7D10016, EBAB03F1

I'm having backups fail on one of my servers. It appears to be failing becase it can't delete the backups on the NAS. Not sure what I need to do to fix it or why it's happening on just this server. Any advice would be most apperciated. The message in the event log is listed below.

--Error E7D10017: Unable to delete '//10.3.50.235/backups/MrDrysDale_SR18/S_filesLevel/File Backup Data/fbfFiles_b23/1d565d006ab2370.fbf'.
---Error E7D10016: Unable to set attributes on '//10.3.50.235/backups/MrDrysDale_SR18/S_filesLevel/File Backup Data/fbfFiles_b23/1d565d006ab2370.fbf'.
----Error EBAB03F1: Following Operating System error occurred while performing requested operation: 'Access is denied.'
---Error E7D10017: Unable to delete '//10.3.50.235/backups/MrDrysDale_SR18/S_filesLevel/File Backup Data/fbfFiles_ef7/1d56506dcaef787.fbf'.
----Error E7D10016: Unable to set attributes on '//10.3.50.235/backups/MrDrysDale_SR18/S_filesLevel/File Backup Data/fbfFiles_ef7/1d56506dcaef787.fbf'.
-----Error EBAB03F1: Following Operating System error occurred while performing requested operation: 'Access is denied.'

(UMI:V-281-2001-23)