Well I doubt that it is talking about different versions of avast, they are essentially the same and if you installed in the default location then there would only be one occurrence of avast. So I think it may be on about a previous AV.
Have (or did) you another AV installed in this system, if so what was it and how did you get rid of it ?
I would suggest a clean reinstall of avast (Home which I think is what you want):
Download the latest version of avast
http://www.avast.com/eng/download-avast-home.html and save it to your HDD, somewhere you can find it again. Use that when you reinstall. Ensure that you scroll down and select the avast direct download link for the English version and not Cnet as that is for an on-line installation (not what you want to do).
Download the avast! Uninstall Utility,
find it here and save it to your HDD.
- 1. Now uninstall (using add remove programs, if you can't do that start from the next step), reboot.
- 2. run the avast! Uninstall Utility, reboot. If step 1 failed it may be necessary to run this from safe mode, once complete reboot into normal mode.
- 3. install the latest version, reboot.
This should ensure that you only have one version, as for the out of date bit, that is entirely possible as the VPS version may not be the latest when obtained from download.com, hence the suggestion to get the full version direct from avast.