Source, and Fix, for Event 8194 VSS "access denied" querying for the IVssWriterCallback

Question

Friends I encountered this error, pasted intact below, just a couple of days ago on a ia64 architecture HP system running Windows 7 Ultimate x64
It appears that I may have a permissions issue somewhere but I do not know how to permanently root-cause-remedy it.  I should note that I do not have any routine backup service running on this particular mule, and no such animal was working at the time
of the issue, so I'm baffled as to what invoked the process.  To anticipate a question you may have:  I did not use on this system a recent "registry cleanup" tool except that which Microsoft uses in a couple of automated packages:  one to do
.NET cleanup, and another to resolve Uninstall/Install issues [this one succeeded... the .NET issue is another story].
This system is a Homegroup owner/creator, but is not on a domain. It is essentially a lab mule that I use for tech work - other windows 7 clients fetch files from it via a bridged wifi AP. 
Thank you in advance for any direction you have for me.
Paste below
twest
Log Name:      Application
Source:        VSS
Date:          8/18/2012 6:36:49 PM
Event ID:      8194
Task Category: None
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      BossHoss-PC
Description:
Volume Shadow Copy Service error: Unexpected error querying for the IVssWriterCallback interface.  hr = 0x80070005, Access is denied.
. This is often caused by incorrect security settings in either the writer or requestor process.
Operation:
   Gathering Writer Data
Context:
   Writer Class Id: {e8132975-6f93-4464-a53e-
1050253ae220}
   Writer Name: System Writer
   Writer Instance ID: {a2af3afe-afb1-4346-bfd6-380873f59328}
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <System>
    <Provider Name="VSS" />
    <EventID Qualifiers="0">8194</EventID>
    <Level>2</Level>
    <Task>0</Task>
    <Keywords>0x80000000000000</Keywords>
    <TimeCreated SystemTime="2012-08-18T23:36:49.000000000Z" />
    <EventRecordID>34091</EventRecordID>
    <Channel>Application</Channel>
    <Computer>BossHoss-PC</Computer>
    <Security />
  </System>
  <EventData>
    <Data>0x80070005, Access is denied.
</Data>
    <Data>
Operation:
   Gathering Writer Data
Context:
   Writer Class Id: {e8132975-6f93-4464-a53e-1050253ae220}
   Writer Name: System Writer
   Writer Instance ID: {a2af3afe-afb1-4346-bfd6-380873f59328}</Data>
    <Binary>2D20436F64653A20575254575254494330303030313236302D2043616C6C3A20575254575254494330303030313231342D205049443A202030303030313235322D205449443A202030303030313236382D20434D443A2020433A5C57696E646F77735C73797374656D33325C737663686F73742E657865202D6B204E6574776F726B53657276696365202020202020202D20557365723A204E616D653A204E5420415554484F524954595C4E4554574F524B20534552564943452C205349443A532D312D352D3230</Binary>
  </EventData>
</Event>
Techwest Resources

Answer 1

Hi,
Firstly, would you please let us know what backup application you do use. Is it the build-in one?
Meanwhile, please refer to
Security Considerations for Requesters for details.
Hope this helps.
Jeremy Wu
TechNet Community Support