NIS 2012 slowing down incoming e-mail .....?

Me, again.

I've just recently installed nis 2012, and since then it seems it's taking A LOT longer for me to receive incoming e-mails....

co-incidence? or does NIS slow it down ...?

I'm using Outlook Express 6 for my e-mail program ( yes, "old school ", I know!!)

comments? help?