Getting error: 535:5.7.8 authentication failed in every outlook send message activity

After migrating to modern folders, i am getting the above error. send outlook message activity is very very important activity in my work flow. all the mail credentials are given correctly . even if i run the process from uipath editor it’s working fine. but i getting this error when tried to run through orchestrator. please solve the problem. on hight priority for me.

Hi @Byra_Padha_Saradhi

The bot machine on which you are running the Automation should contain the Outlook successfully signed in .

Please sign in into Outlook on the Bot machine and try running the Automation.


Yes outlook successfully connected on the machine. even when i run the process from uipath studio its running successfully. but from orchestrator it’s getting error.


Please try Opening the Outlook as Administrator and goto programmatic Access setting and select the third option and try to run the automation

Hope this works,


i forgot to say one thing. some processes are run succesfully. i am getting this error for only some specific processes. i can’t understand why. if the programetic error is there then it can’t work for any process.

Compare the packages in both the projects @Byra_Padha_Saradhi

if its not downgraded kindly upgrade it to latest version and give a try

sir when i tried to use smtp mail message activity in place of outlook mail message activity the process was successfully run. now please suggest me a solution as many no of processes have developed with send outlook mail message activity.

So one clarification @Byra_Padha_Saradhi

to use outlook activities ,

make sure that outlook account has to be signedin in that respective system
so if it has signed in then there would be no problem to use get outlook / send outlook activities

i would request you to manually go and check in that respective machine where mails are getting sent and recieved as expected

Thank you for your response sir.
but i am clearly saying that outlook was configured on my machine. At the same time outlook 2016 software is showing the error
“outlook stopped working . The set of folder can’t be accissible. the output.pst folder is not accsseble.”
is the above error linked to this authentication failed error.

after running the scanpst.exe the outlook works fine. after some time the same error the set of folders not accisble error is displaying.