Use this instead:
[connections width=590 show_alphaindex='true' repeat_alphaindex='true' tray_image_fallback='block' str_bio_head='Volunteer' str_bio_show='Volunteer Detail' str_bio_hide='Close Volunteer Details' str_note_head='Organization' str_note_show='Organization Detail' str_note_hide='Close Organization' str_note_show='Organization']
You do not need to declare default values, which is why I removed them. Also, several of the options were wrapped in fancy quotes. This happens when options are copied from the website. See this QuickTip on working for shortcode. I hope that helps.