Anyway of actually testing which ports are allowed by the ISP?
Clearly my firewall, Zonealarm, is presumably blocking some, but if some are externally blocked it would be interesting to see which. I tried a port scanner and it just said all it tested were blocked so not entirely helpful as one, at least, must be open. I notice also that I cannot get the TBB speedtest to load its java window, it times out - possibly significant. Just tried my FTP program Filezilla, that won't connect so it looks almost certain to be a port issue.
I'd be surprised if it's the blocked SMTP suggested, that wouldn't explain the POP issue.
I'll try asking at reception, assuming they understand the question...