When I try to install ClamWin under Windows XP Home (German version, without SP2) starting clamwin-0.87.1-setup.exe, I get the following error message:
This program requires Windows version 4.1.1998 or later.
On the ClamWin website, however, it says that the program runs under XP.

Any help appreciated.

Kind regards,
Klaus

it does indeed run in xp or 2000. version 4.1 is actually windows 98; windows 2000 or XP is 5.1 and up. Most likely the os detection code is faling because of an incorrect registry entry.

check that this registry key has correct info:

Hive: HKEY_LOCAL_MACHINE
Key: Software\Microsoft\Windows NT\CurrentVersion

CSDVersion = Service Pack
CurrentBuildNumber = build number
CurrentVersion = version number
ProductName = Windows Version name

For windows XP SP2 the values are:
CSDVersion = Service Pack 2
CurrentBuildNumber = 2600
CurrentVersion = 5.1
ProductName = Microsoft Windows XP