Let me disagree with you :)
Compatible with Windows 7, 8, 8.1, 10 in 32 & 64 bits.
This is written at download page. So XP is not supported. And please look at this link - https://toolslib.net/forum/viewthread/3789-ru-dokumentaciya-adwcleaner/ So you can see that in spite of Russian language - site I gave in previous message is quite legitimate and it in accordance with fr33tux at last.
Sandor, 2017-09-01 10:12:33 (UTC)
AdwCleaner is no longer compatible with Windows XP. As linked above, you may still be able to run the 6th branch of AdwCleaner (https://toolslib.net/downloads/viewdownload/1-adwcleaner/files/?s=6&t=release) on XP.
I emphasise on the fact that if your operating system (XP) is infected with an Adware/PUP, AdwCleaner may be able to remediate it, but it will only provide you with a false sense of security since Windows XP is no longer receiving updates from Microsoft (even security fixes).
If you're stuck with it and cannot migrate to a more recent version of Windows (7, 8.1 or 10), I invite you to try Malwarebytes 3.