Undefined index: location_continent (4 replies)

Last night our piwik installation started throwing errors.
No changes were made to the system. It's been working great for a long time.
Most of the errors appear to be related to location_*

I have searched but am unable to find any related fixes. Any help that you can provide in finding a resolution will be greatly appreciated.

There is an error. Please report the message (Piwik 1.8.3) and full backtrace in the Piwik forums (please do a Search first as it might have been reported already!).

Notice: Undefined index: location_continent in /htdocs/piwik/plugins/Live/Visitor.php on line 217

Backtrace -->
#0 Piwik_ErrorHandler(...) called at [/htdocs/piwik/plugins/Live/Visitor.php:217]#1 Piwik_Live_Visitor->getContinent(...) called at [/htdocs/piwik/plugins/Live/Visitor.php:76]#2 Piwik_Live_Visitor->getAllVisitorDetails(...) called at [/htdocs/piwik/plugins/Live/API.php:163]#3 Piwik_Live_API->getCleanedVisitorsFromDetails(...) called at [/htdocs/piwik/plugins/Live/API.php:132]#4 Piwik_Live_API->getLastVisitsDetails(...) called at [:]#5 call_user_func_array(...) called at [/htdocs/piwik/core/API/Proxy.php:190]#6 Piwik_API_Proxy->call(...) called at [/htdocs/piwik/core/API/Request.php:128]#7 Piwik_API_Request->process(...) called at [/htdocs/piwik/core/ViewDataTable.php:422]#8 Piwik_ViewDataTable->loadDataTableFromAPI(...) called at [/htdocs/piwik/core/ViewDataTable/HtmlTable.php:81]#9 Piwik_ViewDataTable_HtmlTable->main(...) called at [/htdocs/piwik/core/Controller.php:152]#10 Piwik_Controller->renderView(...) called at [/htdocs/piwik/plugins/Live/Controller.php:84]#11 Piwik_Live_Controller->getVisitorLog(...) called at [:]#12 call_user_func_array(...) called at [/htdocs/piwik/core/FrontController.php:138]#13 Piwik_FrontController->dispatch(...) called at [/htdocs/piwik/index.php:53]