Hello,
The ".sis" extension stands for "Single Instance Storage". This issue could be happening due to "Single Instance Storage" being installed at some point and then removed incorrectly. The "skipped files" are still pointing to "Single Instance Storage files" that no longer exists.
The "work-around" for this issue is that you could do the following:
Create a folder called SIS Common Store on E drive and
create "10 skipped files " (ie 999edd83-adc8-11d5-9a5a-0090276afa1a.sis )
Now, your jobs should not show an exception regarding the skipped files. If it still does, you could try uninstalling/removing "Single Instance Storage" as per Microsoft Article (http://support.microsoft.com/default.aspx?scid=kb;en-us;299873&Product=win2000 ).
Alternatively refer following technote regarding global exclusion
http://seer.support.veritas.com//docs/264628.htm
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