Hey Jaco,
This should be a simple task, but at least for Microsoft Outlook 2016 it's not (as far as I can tell)...
It should be easily possible to add, subtract, or change to-recipients, but my old code for Microsoft Outlook 2011 doesn't work – hence this work-around.
It's tested with Microsoft Outlook 16.16.27 on macOS 10.14.6 and may require adjusting for different versions of Outlook or macOS.
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# Auth: Christopher Stone
# dCre: 2015/10/15 17:00
# dMod: 2022/01/12 11:24
# Appl: Microsoft Outlook, System Events
# Task: Set To-Field of front draft window to email address 1 if more than 1.
# Tags: @Applescript, @Script, @Microsoft_Outlook, @System_Events, @KMF
# Test: Tested only with Microsoft Outlook 16.16.27 on macOS 10.14.6.
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tell application "Microsoft Outlook"
if class of front window ≠ draft window then
error "Front window is not a draft window!"
else
tell front draft window
if its object = missing value then save
set recipientList to its object's to recipients
if length of recipientList > 1 then
set recipientOne to item 1 of recipientList
set recipientOneEmailAddress to address of (get email address of recipientOne)
end if
end tell
end if
end tell
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tell application "System Events"
if quit delay ≠ 0 then set quit delay to 0
tell application process "Microsoft Outlook"
tell (first window whose subrole is "AXStandardWindow")
tell splitter group 1
tell (first scroll area whose accessibility description is "To:")
tell text area 1
# set toFieldFocus to its focused
set its value to recipientOneEmailAddress
end tell
end tell
# Unnecessary code I left in as an example
# if toFieldFocus then
# tell (first text field whose accessibility description is "Subject:")
# set its focused to true
# end tell
# end if
end tell
end tell
end tell
end tell
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-Chris