RnR trouble ... again

[grumbledook]

I'm using RnR 4.1 on a TP T61P (Vista Ultimate) and an USB disk drive as primary backup location. I was able to create several incremental backups using RnR. And there has been no update or patch of RnR after the last backup. But it doesn't work anymore. What's wrong here?
Here come the respective log entries:

rr.log++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Wed Jan 09 22:14:39 2008 RescueRecovery: \\?\STORAGE#Volume#1&19f7e59c&0&SignatureAD76C9A0Offset7E00Length45DD5A0400#{53f5630d-b6bf-11d0-94f2-00a0c91efb8b}
Wed Jan 09 22:17:16 2008 RescueRecovery: Loc=8 NoPrimary=0
Wed Jan 09 22:17:18 2008 RescueRecovery: BackupThread Started. There are 1 partitions to back up
Wed Jan 09 22:17:18 2008 RescueRecovery: Running: C:\Program Files\Lenovo\Rescue and Recovery\instapps.exe /capture
Wed Jan 09 22:17:29 2008 RescueRecovery: Running: C:\Program Files\Lenovo\Rescue and Recovery\Migration\bin\r2r.exe /c "C:\SWSHARE\capture.sma"
Wed Jan 09 22:28:49 2008 RescueRecovery: Running: C:\Program Files\Lenovo\Rescue and Recovery\br_funcs.exe backup level=3 destination="E:\RRbackups" drive=C: location=8 nice=0 pw=0 uuid=0 compress encrypt
Wed Jan 09 22:28:51 2008 RescueRecovery: br_funcs returned error code 0x58A
Wed Jan 09 22:28:51 2008 RescueRecovery: Backup failed. Free Space High=0x00000030 Low=0xB6546000
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engine.log+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Wed Jan 09 22:28:50 2008 Engine: br_funcs.exe - version is '04.0a.13c.00'
Wed Jan 09 22:28:50 2008 Verbatim: WriteDriveContents(DriveLetter='C:', Dest='E:\RRbackups', Level=3, SleepCount=0, DeviceType=8, dwOptFlags=0x00000001)
Wed Jan 09 22:28:50 2008 SHADOW: Shadow called
Wed Jan 09 22:28:51 2008 SHADOW: Call to InitializeForBackup failed - dwRet = 0x000005a4 - hrRet = 0x8000ffff
Wed Jan 09 22:28:51 2008 SHADOW: Shadow exits with dwRet = 0x000005a4
Wed Jan 09 22:28:51 2008 Engine: CreateShadowCopy fails - 'c:\program files\lenovo\rescue and recovery\shadow.exe create volume=C: identifier=br_funcs directory=C:\A' returned 0x000005a4 - dwRet = 0x0000058a
Wed Jan 09 22:28:51 2008 Verbatim: WriteDriveContents exiting with return code 0x0000058a
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