Google Android support for Microsoft Exchange in pure Google devices - Manual (Page 3)

Important: The other ActiveSync mailbox policies have no effect if this policy is not set.
Require alphanumeric password
If you set this ActiveSync mailbox policy, users must secure their devices using a password that
includes both letters and numbers (only the Password option is available in Settings > Security
> Screen lock).
If you don’t set this mailbox policy, users may secure their devices with a password or a numeric
PIN (both the Password and PIN settings are available).
Number of failed attempts allowed
This ActiveSync mailbox policy sets the maximum number of times a user can enter an
incorrect password before the device resets itself to factory defaults (a local wipe). See Remote
Wipe policy below for details about the effects of the factory data reset performed by a local or
remote wipe.
Pure Google devices support a maximum of 31 failed password attempts for this setting.
Minimum password length
This ActiveSync mailbox policy sets a minimum number of letters or numbers for an PIN or
password.
Pure Google devices support PINs and passwords of up to 16 characters.
Minimum password complex characters
This ActiveSync mailbox policy sets a minimum number of non­letter characters in the
password.
Restrict password history
This ActiveSync mailbox policy prevents users from reusing the last n unique passwords.
Password expiration timeout
This ActiveSync mailbox policy specifies the password expiration timeout. Email will not sync
until the user specifies a new password.
Time without user input before password must be re­entered
This ActiveSync mailbox policy sets the maximum number of minutes after a user has last
touched the screen or pressed a button before the device locks itself. After a lock timeout, the
user must unlock the device with a PIN or password. On pure Google devices, this restricts the