emails from workflow are not being sent

[DannyM1974]

Found a bug? Please fill out the sections below. 👍

Issue Summary

Your help is appreciated. I have a license for a self hosted cal.com. The SMTP settings in .env looks like this:

MAIL_FROM='danny@mydomain.nl'
EMAIL_FROM_NAME='Flexibilivrijheid - Danny van Maanen'
EMAIL_SERVER_HOST='smtp.savvii.nl'
EMAIL_SERVER_PORT=587
EMAIL_SERVER_USER='danny@flexibilivrijheid.nl'
EMAIL_SERVER_PASSWORD=‘z2SD********N!ergGRG34'

When an appointment is booked, no mail is sent. I configured a workflow which should sent a mail to the person who booked the appointment and to me.

Please, would you be so kind to help me solve this issue?

Steps to Reproduce

1. create a workflow
2. trigger is when a new event is booked
3. action 1 = sent mail to attendee (the guest who is booking a time slot)
4. action 2 = sent mail to host (that's me)
5. make a test booking
6. expect mail from action 1 and action 2 to be received, but see that no mail will be received

Any other relevant information. For example, why do you consider this a bug and what did you expect to happen instead?

Actual Results

• I do not receive the mail from action 1 also not from action 2

Expected Results

• Ideal is when I do receive both mails

Technical details

it is a self hosted version of cal.com (© 2026 Cal.com, Inc. v.6.2.0-sh) on a VM on Proxmox with 8Gb memory, 2 CPU and 96Gb bootdisk.

Evidence

• see the information in the steps to reproduce. I tested it several times with different users who booked an appointment.

[Raghvendra2420]

This might be an SMTP configuration issue rather than a Cal.com bug.

One thing that stood out to me is the EMAIL_SERVER_PASSWORD line — it looks like it might be using a curly quote (‘) at the beginning instead of a normal straight quote ('). In some cases, this can break environment variable parsing in Node/Next.js apps, which would cause SMTP authentication to fail and result in no emails being sent.

It might be worth double-checking that the password is using standard quotes (or no quotes at all) and then restarting the service.

If that doesn’t resolve it, feel free to share any logs or error messages here . I’d be happy to take a closer look.

[DannyM1974]

Hello, Thank you for your answer, I appreciate your help. I checked the Mail settings and discovered a stupid mistake from my side. The SMTP server is not an .nl server….. It is: EMAIL_SERVER_HOST=‘smtp.savvii.email' Now I tested again and mail is being sent. But something else is strange. When I book a new appointment, it takes a while with a spinning confirm button before a get an error. The booking cannot be made because: the string did not match the expected pattern. Nevertheless, the appointment has been saved in the system and the mail has been sent. Could it be that an SMTP server host ending with .email is a bit strange and the system is not used to it? :-) Please, let me know how I can get some logging or other information with which you are able to troubleshoot. Thank you in advance for your reply. Best regards, Danny van Maanen

…

Op 21 apr 2026, om 13:18 heeft Raghvendra2420 ***@***.***> het volgende geschreven: Raghvendra2420 left a comment (calcom/cal.diy#28940) <#28940 (comment)> This might be an SMTP configuration issue rather than a Cal.com bug. One thing that stood out to me is the EMAIL_SERVER_PASSWORD line — it looks like it might be using a curly quote (‘) at the beginning instead of a normal straight quote ('). In some cases, this can break environment variable parsing in Node/Next.js apps, which would cause SMTP authentication to fail and result in no emails being sent. It might be worth double-checking that the password is using standard quotes (or no quotes at all) and then restarting the service. If that doesn’t resolve it, feel free to share any logs or error messages here . I’d be happy to take a closer look. — Reply to this email directly, view it on GitHub <#28940?email_source=notifications&email_token=CCBTIJDRJYXFNNA2ZQFGZXL4W5KHZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMRYHAYTANBWHEZ2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-4288104693>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CCBTIJDCNQVHL7LDKXIXMQT4W5KHZAVCNFSM6AAAAACX7MESVCVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DEOBYGEYDINRZGM>. You are receiving this because you authored the thread.

[DannyM1974]

Hello, I did some more testing and it seems that an SMTP host address ending with .email is a problem voor Cal. When I use another SMTP host ending with .nl it works like a charm. It would be great if the self hosted Cal can be changed so it will also accept SMTP hosts ending with .email because then I can sent emails as from my domains. Otherwise, the sender cannot be from my own domain because it violates with DMARC policy. Thank you in advance for your help and your reply. Best regards, Danny van Maanen

…

Op 21 apr 2026, om 14:51 heeft Catch Danny van Maanen ***@***.***> het volgende geschreven: Hello, Thank you for your answer, I appreciate your help. I checked the Mail settings and discovered a stupid mistake from my side. The SMTP server is not an .nl server….. It is: EMAIL_SERVER_HOST=‘smtp.savvii.email' Now I tested again and mail is being sent. But something else is strange. When I book a new appointment, it takes a while with a spinning confirm button before a get an error. The booking cannot be made because: the string did not match the expected pattern. Nevertheless, the appointment has been saved in the system and the mail has been sent. Could it be that an SMTP server host ending with .email is a bit strange and the system is not used to it? :-) Please, let me know how I can get some logging or other information with which you are able to troubleshoot. Thank you in advance for your reply. Best regards, Danny van Maanen > Op 21 apr 2026, om 13:18 heeft Raghvendra2420 ***@***.***> het volgende geschreven: > > > Raghvendra2420 > left a comment > (calcom/cal.diy#28940) > <#28940 (comment)> > This might be an SMTP configuration issue rather than a Cal.com bug. > > One thing that stood out to me is the EMAIL_SERVER_PASSWORD line — it looks like it might be using a curly quote (‘) at the beginning instead of a normal straight quote ('). In some cases, this can break environment variable parsing in Node/Next.js apps, which would cause SMTP authentication to fail and result in no emails being sent. > > It might be worth double-checking that the password is using standard quotes (or no quotes at all) and then restarting the service. > > If that doesn’t resolve it, feel free to share any logs or error messages here . I’d be happy to take a closer look. > > — > Reply to this email directly, view it on GitHub <#28940?email_source=notifications&email_token=CCBTIJDRJYXFNNA2ZQFGZXL4W5KHZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMRYHAYTANBWHEZ2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-4288104693>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CCBTIJDCNQVHL7LDKXIXMQT4W5KHZAVCNFSM6AAAAACX7MESVCVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DEOBYGEYDINRZGM>. > You are receiving this because you authored the thread. >

[DannyM1974]

Hello, I also contacted the company which hosts my domain. Besides a .email SMTP host they provided me also this SMTP host address: lba-sov.soverin.net <http://lba-sov.soverin.net/> I tested it, but also this gives in Cal the error: “The string did not match the expected pattern." Best regards, Danny van Maanen

…

Op 21 apr 2026, om 16:15 heeft Catch Danny van Maanen ***@***.***> het volgende geschreven: Hello, I did some more testing and it seems that an SMTP host address ending with .email is a problem voor Cal. When I use another SMTP host ending with .nl it works like a charm. It would be great if the self hosted Cal can be changed so it will also accept SMTP hosts ending with .email because then I can sent emails as from my domains. Otherwise, the sender cannot be from my own domain because it violates with DMARC policy. Thank you in advance for your help and your reply. Best regards, Danny van Maanen > Op 21 apr 2026, om 14:51 heeft Catch Danny van Maanen ***@***.***> het volgende geschreven: > > Hello, > > Thank you for your answer, I appreciate your help. > > I checked the Mail settings and discovered a stupid mistake from my side. The SMTP server is not an .nl server….. It is: EMAIL_SERVER_HOST=‘smtp.savvii.email' > > Now I tested again and mail is being sent. But something else is strange. When I book a new appointment, it takes a while with a spinning confirm button before a get an error. The booking cannot be made because: the string did not match the expected pattern. > > Nevertheless, the appointment has been saved in the system and the mail has been sent. Could it be that an SMTP server host ending with .email is a bit strange and the system is not used to it? :-) > > Please, let me know how I can get some logging or other information with which you are able to troubleshoot. > > Thank you in advance for your reply. > > Best regards, > > Danny van Maanen > > >> Op 21 apr 2026, om 13:18 heeft Raghvendra2420 ***@***.***> het volgende geschreven: >> >> >> Raghvendra2420 >> left a comment >> (calcom/cal.diy#28940) >> <#28940 (comment)> >> This might be an SMTP configuration issue rather than a Cal.com bug. >> >> One thing that stood out to me is the EMAIL_SERVER_PASSWORD line — it looks like it might be using a curly quote (‘) at the beginning instead of a normal straight quote ('). In some cases, this can break environment variable parsing in Node/Next.js apps, which would cause SMTP authentication to fail and result in no emails being sent. >> >> It might be worth double-checking that the password is using standard quotes (or no quotes at all) and then restarting the service. >> >> If that doesn’t resolve it, feel free to share any logs or error messages here . I’d be happy to take a closer look. >> >> — >> Reply to this email directly, view it on GitHub <#28940?email_source=notifications&email_token=CCBTIJDRJYXFNNA2ZQFGZXL4W5KHZA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIMRYHAYTANBWHEZ2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-4288104693>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CCBTIJDCNQVHL7LDKXIXMQT4W5KHZAVCNFSM6AAAAACX7MESVCVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHM2DEOBYGEYDINRZGM>. >> You are receiving this because you authored the thread. >> >