I'm a Stake Clerk ( Technology Specialist ) who has a couple FROM our Stake ... serving a Full-Time Mission ... IN our Stake. Their situation is identical to "PapaNoHair" who has made the posts above.
Their Android Phones and Tablets won's sync LDS Tools ... but only SINCE their call as missionaries ... it worked perfectly before their call.
Now as trouble shooters, you're going to ask me about their Android devices, what OS are the devices using, who are their carriers ( Verizon, At&T, T-Mobile), etc.
I ERASED an iPod and 2 Android Phones ( both with different carriers and differing OS Versions ) and an Android Tablet ( with still a another Android OS ) ...
ALL of the devices would sync LDS Tools if I use MY LDS Username and Password. All of the Androids fail if I use either of the LDS Usernames of the Couple Serving the Full-Time Mission in their OWN Stake ... BUT ... on the Apple iPod everything works, with everyone's Usernames and Passwords all the time ...
So ... if a person is 1. Serving a Full-Time Mission is the same Stake in which they Reside ... and 2. Is using an Android Device ... LDS Tools will not download onto their device ... until after they are released, and become full-time members of their home unit.
However ... if they are using an Apple Device ... there is no problem.
And this wouldn't be a big issue EXCEPT that the Church is moving away from Apple and adopting Androids more and more ... so this problem will occur more often in the future.