ZTE blade Android 7.1

.I have a ZTE blade (z557bl) it runs Android 7.1.1 ...I need to install Google account manager 5.1.1 to remove the email password option and bypass through the web browser sign in...
Now the problem is that the phone says the 5.1.1 apk file is corrupt and won't install after I download it. Research indicates that the phone is preventing me from downgrading to an older version...
I am 95% complete with this process and I can't get the corrupt file to install...any assistance would be greatly...

ZTE blade Android 7.1

from DroidForums.net | Android Forums & News https://ift.tt/2KerYV3
via IFTTT