Cannot backup or browse Oracle database: "Error processing request" (4040874)

When browsing an Oracle database from the Web UI the following pop up message is returned:

“Error processing request”

Scheduled jobs keep failing with the following log entries:

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Failed to list of threads assuming a single thread

Failed to get list of tablespaces using backup list

Failed to start to save copy of control file

Failed to switch log file

Failed to Save file list

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Trace shows the Oracle plugin master process fails to start the nvoracleclient11g.exe:

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5             PROCESS             ???         8452      280        0             115113574869   CreateProcess: 'C:/Program Files/Quest/NetVault Backup/bin/nvoracleclient11g.exe'

0             SYSEXEC              ???         8452      221        0             115113768251   Failed with exit code 255

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