When I opened it there was a Trojan virus. :P
Lol anyone can make this with Cheat Engine in 5 mins and yes its VAC detected its been for years, its just a memory edit that changes the value of r_drawothermodels from 1 to 2
EDIT: and its probably binded with a virus because it shouldnt be detected as it is a cheat engine trainer
how do i open the attachment.php file
You don't, the attachment.php should've redirected you to the actual download but for some reason did not.
Try and re-downloading the file.
* I wouldn't recommend using this file as it has been filed as detected.