Event ID 517 The Audit was Cleared?

Secrios

Distinguished
Sep 3, 2011
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So I cleared my event viewer logs and saved backups for them. However when I went to a system restore point I received an event error called escent 517. I did a little digging and maybe I shouldn't have cleared the security audit history.

In the error it refers to a file called SRUdb.dat

How serious is this? Does it stop me from using restore points? Will this mean the computer won't recognise me as one of it's users? How broken is it? Can it be fixed?