升級後不知道過了多久突然Web管理介面進不去，只會顯示"the server is temporarily unable to service your request due to maintenance downtime or capacity problems. please try again later."
後來爬英文論壇找到降韌體的方式
https://wiki.qnap.com/wiki/Manually_Updating_Firmware
降回4.3.5.0760 build 20181114就正常了
從 APP 打開
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