This post would describe how conventionally a SharePoint site is backed up from one farm and restored into another farm where the SharePoint farm versions could be different.
I was having a difficult situation when my site collection restore gave me this error.
It basically describes that the backup of the web application that I took was running on a farm with a different SharePoint version. I checked and verified that both had SharePoint 2010 and had SP1 installed recently.
Follow the steps to resolve this problem.
1. Make sure that the farm versions are the same. This can be achieved by going to Central Administration – > System Settings -> Manage Servers in this farm
2. Checking the Farm versions in the different farms, I was able to find that the SharePoint farm versions were different.
3. I started the SharePoint Configuration wizard on the first server and I could see that there were some changes happening. This could be the step many of us could miss. We need to run the SharePoint Configuration wizard after an SP1 upgrade.
4. I did the same for both the farms and noticed that the Farm versions were the same now.
5. I then did a backup of the site collection using stsadm from the first farm and restored into the second farm. Everything went right this time.