Just wondering if anyone was having trouble receiving emails to their iserve email accounts, from some companies, such as NZ post. eg name@nzpost.co.nz  Was told by NZ post that they emailed me several times with some important emails, but I don't have any record of receiving the emails. I got them to send me a test email while on the phone to them, and it also didn't come through.. I do also use D2S if that makes any difference, and the emails aren't in the spam or good folders. 
The IP that they say they are sending from is 202.12.251.50, and it doesn't look to be blacklisted.
Can anyone help? Business hosting support is now closed until monday.