This is the message that appears, in red - “ArgumentNullException: Value cannot be null. Parameter name: s”
Please assist as soon as you can - I need to print, scan and send quotes, delivery notes and invoices but month end coming up as well. Please help.
I can’t troubleshoot your email problems. But if your software is up to date, you can generate PDF’s directly from Manager and email them outside the program. Even if your software is out of date, you can “print to PDF.” Depending on your operating system, that capability might be built into your print dialog or you may need a 3rd-party PDF driver.
I have seen that this can be done as well - I have been using this method for all this time but this is a new problem which I would like resolved. The error message appears on manager as I click send so I don’t think this is an email problem.
I am also facing the same problem. Sending email has been fine and now when I click ‘Send’ I also get the message:
ArgumentNullException: Value cannot be null. Parameter name: s
I am using Manager 16.10.55
@pottstech, for the time being, you will need to print the pdf and then email it outside of Manager.
I suspect that the error is related to the current pdf generating service and once @lubos is happy to convert all reporting to the new internal pdf mechanism, I’m sure emailing will then resume working again.
Thank you for your reply @Zark I have been pressing the PDF button and emailing invoices manually as you have suggested.
I will continue this way until the problem is resolved. I hope that @lubos can post in this thread to let us know when it should be working again. Have a nice day 
The error you are getting has nothing to do with internal PDF generator, especially if PDF button works.
Go to Email Settings under Settings tab. It seems like you are using custom SMTP server and it’s misconfigured? (e.g. Host not being filled in.)
@lubos, does the Email button now use the internal PDF generator?
Yes, it uses internal PDF generator now. With one small exception - if you have custom HTML invoice, for those invoices, it will still use external PDF service to convert.
Aaah. Awesome… It was still timing out for me using the default email settings (no smtp), which used to work fine.
I just set up the SMTP server and now it is working fine. Thank you.
Hi @lubos . I’m still getting the error message. I have tried using two custom mail servers.
One, which doesn’t require authentication because it’s the ISP I’m currently connected too - test works successfully and I receive the test email at my gmail and pottstech email account
Two, a completely different domain in which I manage (I am a web designer and hostmaster) and does require authentication and the test email from the email settings is also successful.
The issue is only when you click send on an invoice or other document I’m trying to send.
I’m not using a custom HTML invoice.
ArgumentNullException: Value cannot be null. Parameter name: s - is display regardless of whether I use a custom SMTP mail server or not.
Thanks for looking into this.