Hi,
Please check if you can find the pathword from below paths:
/Users/$USER/Library/Containers/com.microsoft.rdc.mac/Data/Library/Preferences/com.microsoft.rdc.mac.plist
Applications/Utilities/Keychain Access
For your reference: https://apple.stackexchange.com/questions/182209/where-does-microsoft-rdp-8-for-mac-store-its-configuration/182258
Hope the information helps.
Thanks,
Eleven
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