Error during mailsending

Hello, during mailsending I receive an error code: “-ERR What? sc=BVXxofuYNCgI_151531_8m”
Would appreciate for your comments what is it and how it should be solved.

Hello Natalia,
unfortunately I haven’t encountered this issue before, so please provide more information concerning your problem.
What version of eM Client are you currently running? Please check the exact version number in Help>About section.
What mail account were you sending the message from?
Is this the full content of the error message?

Regards,
Olivia

Dear Olivia.
Please note that release number is 6.0.24928.0.
Below you will find corresponding screenshot.

Thank you