Hi, first of all: I'm not a native english speaker so I apologize in case my english might be incorrect sometimes.

Thanks to the process monitor which was mentioned in another thread I've found a way to install Antivir Personal Edition which I want to share with you.

It's pretty simple and might work with other programms which check for a Server OS and deny the installation too.

1.) Start --> Run --> Regedit
2.) Go to HKEY_LOCAL_MACHINE --> SYSTEM --> CurrentControlset --> Control
3.) Now change the permissions of the folder "ProductOptions" --> add your user account (for example Computername\Username) and deny yourself the read rights for the whole folder. Be careful not to deny the whole rights for all administrators or something like that (I tried that first cause of a black out and it leads to windows not being able to boot).
4.) Now you should be able to install Antivir PE

In case you want to revert the permission settings just log to your administrator account. Here you can again grant your user account full rights for "ProductOptions".

Up until now I didn't notice any drawbacks but I won't garantie that there might be some.

Nice explanation, I didn't know this trick! Added a link to this at the Security Software Compatibility page for Avira AntiVir Personal.

Though in another thread you gave "steve" the important hint to use the process monitor (quite a nice tool btw, I wouldn't want to miss it from now on ^^) .

By the way: Before I remembered that it won't work with vista anyway a few minutes ago I noticed that I could install Sunbelt Kerio PE like that too. So it might work for several other programs too.

yeah, Process Monitor is a *must have* for experimenting with programs and tracing errors!
I still wonder what's so special with the HKLM\SYSTEM\CurrentControlSet\Control key and subkeys in the registry! I'd rather think that programs check out the HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion (and HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion in x64 edition) when checking for the OS version, but I am glad this works for several programs!

To be honest the keys and subkeys you've mentioned were the first ones I tried too (I also thought that they might be the logical choice for a program checking the OS type) but that didn't seem to have any impact on the Antivir installer while the "ProductOption" keys worked.
But maybe, there might also be programs, on which changing the "CurrentVersion" keys and subkeys is the important step to install them.

Up until now, I didn't notice much programs that denied the installation after tweaking the .msi anyway So my experience just relies on Antivir PE and Sunbelt Kerio PE (which won't work under Vista anyway ^^).

I tried this with the Antivir PE and it didn't work. I changed the keys you listed, restarted, tried to install, still gave me the "does not run on server OS" message. I double checked I changed everything and tried again, no go.

Also tried it with several other security apps (onecare, AVG) and it didn't work there either. Are you sure you listed all of the changes that you need to make?

Thanks

Hmm... let me think about it. Are you sure you denied the read rights to the same account you were logged on when you tried to install Antivir PE?

On a second thought it might also depend on the group membership of your account. In my case, my account on which I tried this is an account with administrator rights (other than the standard "Administrator" account). Maybe if you try this with a non-administrator account the read deny will not work because the program can bypass this.

I'll try to set up a clean VMWare virtual machine and make some tests today or tomorrow (I'll also try other programs like Avast Home and AVG Free).

Ok, I've tried it now with a fresh and clean Windows Server 2008 x64 VMware virtual machine and it seems to be like I assumed: The account on which you want to install Antivir PE and which read rights you deny has to be an administrator-type account (at least until the installation is complete). Otherwise (with normal user rights) it definitly didn't work.

Plus, I've tried to install AVG Free and Avast Home and here are the results:

- The installation of Avast Home works with this registry tweak too
- The installation of AVG Free doesn't seem to rely on the "ProductOptions"-Key so in other words: It won't work like this

So it's now at least 2 of 3 free antivirus softwares which work with Windows Server 2008

Yes, silly of me, It was a user account i was trying to install it with. I shall try the admin account now thanks

Nice work Scimitar! This trick allowed me to install Avast Home in Server 2008 Enterprise (64 bit). Afterwords I logged into the master Admin account and reset the permissions. So far so good!