I have been getting this pop-up about once every two hours, for a good six months. What is it, and how do I make it stop? Problem details are below. Many thanks.

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Problem signature:
Problem Event Name: CLR20r3
Problem Signature 01: updater.exe
Problem Signature 02: 2.0.8100.0
Problem Signature 03: 51da5d04
Problem Signature 04: System.Xml
Problem Signature 05: 4.0.30319.34281
Problem Signature 06: 565e85f1
Problem Signature 07: 985
Problem Signature 08: 27
Problem Signature 09: System.Xml.XmlException
OS Version: 6.3.9600.
Locale ID: 1033
Additional Information 1: c541
Additional Information 2: c54150a41eb70a5fb5e78be58e2eab6d
Additional Information 3: bd96
Additional Information 4: bd96a2183e453a37ba51351467048d4e

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