If you are forced to use XP, . Siemens released version 3.0 of the USB A2 driver, but that version removed XP support entirely (min OS is Windows 7).
The Simatic PC Adapter USB A2 Go to product viewer dialog for this item. Simatic Pc Adapter Usb A2 Driver Windows Xp
On systems where STEP 7 is already installed, drivers may be located at C:\Program Files\Siemens\Common\S7SDD . Troubleshooting Tips If you are forced to use XP,
Setting this up on XP is easier than modern OSs, but there is a specific order you must follow to avoid the dreaded "Driver Not Found" loop. Simatic Pc Adapter Usb A2 Driver Windows Xp
Need to migrate away from XP? Consider upgrading to a Siemens USB A2 driver for Windows 10 (still compatible with Step7 V5.6) – but that’s a story for another article.