IncrediMail is great eye candy, but an average, at best, email client. Not friendly to either the system or to other email software of any sort (especially other email clients) It’s formats are recognized by no one but IncrediMail.
It is also, extremely resource intensive and seriously bloats the Windows registry with junk used only to further its own needs.
The biggest price you’ll pay (whether you get it ’free’ [ha!, ha!, nothing is free], or buy an upgrade), is when/if you finally decide it’s not worth using. You’ll uninstall, but you’ll be left with the dross! This includes >512Kb of registry junk! And for that you’ll have 3 choices:
1) Typical registry utility/cleaner (probably won’t work)
2) Software dedicated to cleaning up after IncrediMail (yes, there’s a demand, so this software does exist - may not work)
3) Clean it up yourself with a registry editor (works only if you know what you’re doing in the registry, else may screw up your whole system)
Sounds pretty glum? Yup! It is!