Sending is inconsistant

I realized that my recipients are  sometimes not getting mail I send, even though it shows up in my “sent” folder.  I do not get any errors.  I have tried sending test e-mails to another account of mine, sometimes they go through, sometimes they don’t.  I ran diagnostics in the “accounts” section… no issues.  I haven’t changed anything with my settings lately.  Any ideas?

Hello Amy, what version of eM Client are you currently using on your computer, can you please check the exact release number in Help > About? What mail service are you using with eM Client? Are you using any security software on your computer, that may be blocking the application’s ability to connect to the server?

Thank you,