I have an external email account hosted on IMAP port 993. When I have my laptop connected to home wifi I'm unable to receive emails on my phone or laptop.
If I switch to use my phone as a wifi hotspot then my laptop email immediately works without changing any settings. Also my phone receives email over 4G rather than WiFi.
I've looked on the router and tried disabling the firewall (only as a test, not as a permanent fix) and that made no difference, IMAP connection (using SSL on TCP port 993) still doesn't work.
Any suggestions? I've checked with the hosting provider and they claim they aren't blocking my IP.
They may claim that, but it is the most likely cause. You could try getting a different public IP address by disconnecting your hub from line for half an hour or so
I've just tried this and confirmed that I have a new public IP but I'm getting the same issue.
I'll go back to the hosting provider and confirm they're not blocking a whole range somehow .
Is there nothing on the router which could be having an effect?
No, there will be no settings affecting access.
I access an external IMAP server on port 993 as I'm sure many other customers do with no problems.
Just a thought, are you using a VPN?