Partition backups stopped working in new year

Update. I deleted the metadata on the backup partition and it works now.

I can't get any of my scheduled nor manual backups to run in the new year. I downloaded and installed v13762 over my 12497. Still no help. Below is the log alert I need help to overcome:
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Log Entry Details
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Type: Error
Date and time: 01/05/14 18:12:33
Backup plan: E6510 Weekly C:\ Backup
Task: Full backup
Code: 11,863,304(0xB50508)
Module: 181
Owner: Lefty@FRANK-LAP
Message:
Task 'Full backup' failed: 'Invalid URI.
Additional info:
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Error code: 9
Module: 161
LineInfo: ca40e4ee016a248e
Fields: IsReturnCode : 1, $module : C:\Program Files (x86)\Acronis\BackupAndRecovery\mms.exe
Message: Invalid URI.
--------------------'.
Acronis Knowledge Base: http://kb.acronis.com/errorcode/

Event code: 0x00A10009

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