@Dilan Nanayakkara , Based on my testing, when we set the outlook default email account as the company email account, the picture sharing will go to the company email account firstly which makes the data considered as corporate and unable to share it to personal email account. But when I change the outlook default account to personal email account, the picture sharing will firstly go to personal email account and it can select to change sharing to company email account. So I think this is our issue. We can change the outlook default email account to personal one under outlook settings to see if can work.
Hope it can help.
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