SQL Server Backup Jobs Failing. The error seems to be related to MaximumErrorCount, but I am not sure how to fix value or if changing it will resolve?

My backup jobs are failing with following error when check it's history. I have already checked this link regarding maximumerrorcount value: [SQL Server 2008 - Change the MaximumErrorCount or fix the errors](https://stackoverflow.com/questions/3250648/sql-server-2008-change-the-maximumerrorcount-or-fix-the-errors) . At this point I'm not sure what to do if maximumerrorcount is only masking the actual problem. Log job history (DB_TaxExemption_BKP.Subplan_1): > Step ID 1 Server INHOUSE-DB Job Name DB_TaxExemption_BKP.Subplan_1 > Step Name Subplan_1 Duration 00:00:00 Sql Severity 0 Sql Message ID 0 > Operator Emailed Operator Net sent Operator Paged Retries Attempted 0 > Message Executed as user: NT AUTHORITY\LOCAL SERVICE. Microsoft (R) > SQL Server Execute Package Utility Version 14.0.1000.169 for 64-bit > Copyright (C) 2017 Microsoft. All rights reserved. Started: 10:12:00 > PM Error: 2022-03-30 22:12:00.47 Code: 0xC00291EC Source: > {4D6AAF94-D3FC-4873-9F66-E35E323A6BEE} Execute SQL Task Description: > Failed to acquire connection "Local server connection". Connection may > not be configured correctly or you may not have the right permissions > on this connection. End Error Warning: 2022-03-30 22:12:00.47 Code: > 0x80019002 Source: OnPreExecute Description: SSIS Warning Code > DTS_W_MAXIMUMERRORCOUNTREACHED. The Execution method succeeded, but > the number of errors raised (1) reached the maximum allowed (1); > resulting in failure. This occurs when the number of errors reaches > the number specified in MaximumErrorCount. Change the > MaximumErrorCount or fix the errors. End Warning Error: 2022-03-30 > 22:12:00.48 Code: 0xC0024104 Source: Back Up Database (Full) > Description: The Execute method on the task returned error code > 0x80131904 (Login failed for user 'backupuser'.). The Execute method > must succeed, and indicate the result using an "out" parameter. End > Error ## Heading ##Error: 2022-03-30 22:12:00.48 Code: 0xC0024104 > Source: {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX} Description: The > Execute method on the task returned error code 0x80131904 (Login > failed for user 'backupuser'.). The Execute method must succeed, and > indicate the result using an "out" parameter. End Error Warning: > 2022-03-30 22:12:00.48 Code: 0x80019002 Source: OnPostExecute > Description: SSIS Warning Code DTS_W_MAXIMUMERRORCOUNTREACHED. The > Execution method succeeded, but the number of errors raised (2) > reached the maximum allowed (1); resulting in failure. This occurs > when the number of errors reaches the number specified in > MaximumErrorCount. Change the MaximumErrorCount or fix the errors. End > Warning DTExec: The package execution returned DTSER_FAILURE (1). > Started: 10:12:00 PM Finished: 10:12:00 PM Elapsed: 0.219 seconds. The > package execution failed. The step failed I know for sure that the user for this backup job is sysadmin and it is not locked out all rights are grated. And this is production so I cannot take many risks. What am I missing ?