If you have gotten the following message:
Failed to parse detail: START_TAG seen …</sf:exceptionMessage><sf:upgradeURL>… @1:752 due to: com.sforce.ws.ConnectionException: unable to find end tag at: START_TAG seen …</sf:exceptionMessage><sf:upgradeURL> … @1:752
Or something like that while trying to load in to Salesforce.com Data Loader, try upgrading your version. I had 35.00 and 37.00 both fail where a fresh copy of 38.00 worked.
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