Windows xp compatibility

Windows XP has no support for .NET Framework 4.5.

SambaPOS 4 (and 5) requires .NET 4.5

The root of the issue is a compatibility problem between XP and .Net 4.5

The simple answer to your question is No. You cannot install SambaPOS 4 (or 5) on Windows XP. You must use Windows 7 or greater.

XP is not compatible with many applications. There is no good reason to run XP in this day and age.