I am running:
SugarOS 4.5.0e
PHP 4.4.2
MySQL - 5.0.22-community-nt
IIS 6.0

When viewing a contact I tried to click on View Summary under the History tab. I get the following error messages in the popup window:

Notice: Undefined index: MySettings in D:\sugarcrm\modules\Activities\Popup_picker.php on line 47

Notice: Undefined index: in D:\sugarcrm\modules\Activities\Popup_picker.php on line 48

Fatal error: main(): Failed opening required '' (include_path='.;c:\php\includes') in D:\sugarcrm\modules\Activities\Popup_picker.php on line 48