Validate failure but backup successful on Mailbox Backup

Hello;

I get the same error every night on the Exchange mail backup. We are backing up to disk, and we rotate through 5 different external drives on a daily basis, so it's not drive specific. System backups are fine. Here are the error logs:

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Log Entry Details
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Type: Information
Date and time: 12/29/2014 8:00:02 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,682(0x135003A)
Module: 309
Owner:
Message:
Command 'Running backup plan 'Weekday Exchange Mailbox Backup'' is running.
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Log Entry Details
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Type: Information
Date and time: 12/29/2014 8:00:07 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,682(0x135003A)
Module: 309
Owner:
Message:
Command 'Backing up' is running.
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Log Entry Details
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Type: Information
Date and time: 12/29/2014 11:18:45 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,683(0x135003B)
Module: 309
Owner:
Message:
Command 'Backing up' has completed successfully.
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Log Entry Details
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Type: Information
Date and time: 12/29/2014 11:18:45 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,683(0x135003B)
Module: 309
Owner:
Message:
Command 'Backing up' has completed successfully.
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Log Entry Details
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Type: Information
Date and time: 12/29/2014 11:18:51 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,682(0x135003A)
Module: 309
Owner:
Message:
Command 'Replicating backups/cleaning up archives (1st location)' is running.
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Log Entry Details
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Type: Information
Date and time: 12/29/2014 11:18:53 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,682(0x135003A)
Module: 309
Owner:
Message:
Command 'Validating' is running.
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Log Entry Details
--------------------
Type: Information
Date and time: 12/29/2014 11:18:51 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,682(0x135003A)
Module: 309
Owner:
Message:
Command 'Replicating backups/cleaning up archives (1st location)' is running.
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Log Entry Details
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Type: Error
Date and time: 12/29/2014 11:24:14 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,685(0x135003D)
Module: 309
Owner:
Message:
Command 'Validating' has failed.
Additional info:
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Error code: 61
Module: 309
LineInfo: 4a8728dc8a1c950f
Fields: $module : service_process_vs_32308
Message: Command 'Validating' has failed.
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Error code: 1
Module: 309
LineInfo: e083d6465b83d2
Fields: $module : service_process_vs_32308
Message: bad allocation
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Acronis Knowledge Base: http://kb.acronis.com/errorcode/

Event code: 0x0135003D+0x01350001

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Log Entry Details
--------------------
Type: Error
Date and time: 12/29/2014 11:24:14 PM
Backup plan: Weekday Exchange Mailbox Backup
Task: Incremental backup
Code: 20,250,685(0x135003D)
Module: 309
Owner:
Message:
Command 'Running backup plan 'Weekday Exchange Mailbox Backup'' has failed.
Additional info:
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Error code: 61
Module: 309
LineInfo: 4a8728dc8a1c950f
Fields: $module : mms_vs_32308
Message: Command 'Running backup plan 'Weekday Exchange Mailbox Backup'' has failed.
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Error code: 41
Module: 307
LineInfo: e6792a5ee190dda7
Fields: $module : agent_protection_addon_vs_32308
Message: ProtectCommand: Failed to execute the command.
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Error code: 1
Module: 309
LineInfo: e083d6465b83d2
Fields: $module : service_process_vs_32308
Message: bad allocation
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Acronis Knowledge Base: http://kb.acronis.com/errorcode/

Event code: 0x0135003D+0x01330029+0x01350001

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Any assistance here would be appreciated. Thanks.