I frequently get a runtime exception when I edit visualforce pages in Welkinsuite.
The exception message says:
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An exception has been encountered. This may be caused by an extension.
You can get more information by examining the file
'C:\Users\rmahendravada\AppData\Roaming\Microsoft\AppEnv\12.0\ActivityLog.xml'
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It's frustrating. I have attached a screenshot and the ActivityLog.xml file.