Solved: Getting Internal Server Error on order verification

[The Yellow Fellow]

J 3.8.13 / VM 3.4.2 / PHP7.2.10

I'm experiencing an issue that when a user clicks the Verify order button, after a 30 second timeout they get a 500 Internal Server Error.
I've set shipping and payment to automatic default (payment is handled outside VM afterwards)

In my webserver error log there's:
mod_fcgid: read data timeout in 45 seconds, referer: [MY CART URL]
End of script output before headers: index.php, referer: [MY CART URL]

I've tried reverting back to VM 3.4.0 or PHP5 but that didn't help...

Any ideas?

[GJC Web Design]

have u set a dummy payment method (standard)?

[The Yellow Fellow]

Yes I did

[The Yellow Fellow]

I solved it!
Turns out not being able to send the confirmation emails caused the timeout. I changed the joomla mail settings to use phpmailer (the test site on my dev web server uses smtp) and it works.