Error: The SMTP server requires a secure connection or the client was not authenticated The server response was 5.5.1 Authentication Required in ASP.Net

JOYSON

Please refer the follwing link

when the registeration completes I get error like this

"The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required"

I have error screenshot in here please see the link

I have tried so many methods like truning on less sequre apps in gmail etc...

but the error is still not going please help me

dharmend...

0 1

Refer below article.

I agree, here is the link: https://www.e-iceblue.com/Introduce/spire-office-for-net-free.html

GMAIL Error: The SMTP server requires a secure connection or the client was not authenticated