Double-check that the downloaded version supports Android 7.1 (API 25). If you mistakenly downloaded a version compiled exclusively for Android 8.0 or higher, it will trigger this error.
Search for "Google Play Store" and select a version that lists as the minimum requirement.
Android Tips
You should only download APKs from reputable sites to avoid malware:
In some cases, you may need to clear the Play Store app's cache and data: google play store apk download for android 7.1.2
Toggle the switch next to to the "On" position.
When downloading, look for the variant that lists "for Android 7.0+ (Nougat, API 24/25)". Double-check that the downloaded version supports Android 7
Rooted users might accidentally remove core system files.