症狀
在 Microsoft Exchange Server 2019 中使用 Set-ExchangeServer -InternetWebProxy 指令碼設定代理伺服器後，現代附件功能就無法運作了。 如果您在 Outlook on the Web 寄出帶有現代附件的電子郵件， (OWA) ，則會記錄以下事件：
From: Microsoft Outlook <microsoftexchange329e71ec88ae4615bbc36ab6ce41109e@contoso.com>
To: <the user who just sent out a modern attachment>
Subject: Your recipients couldn't be given access to the file <file name>
Body: The location where the file is stored isn't available.
The message was sent, but recipients might not be able to access the attachment.
Try opening the file <filename> and giving others access to it from its current location.
解決方式
要解決這個問題，請安裝以下累積更新：
Exchange Server 2019 的累積更新 14 或 Exchange Server 2019 的後續累積更新