Contacts app not showing all contacts! I sync'd my PC-based Outlook contacts with my Sony Xperia XA, using MyPhoneExplorer.  It tells me 3526 contacts are sync'd, and in checking the phone with ContactsOptimizer, it reports the same number.  When I open the Contacts app, it does not show some of my contacts! I discovered this, because the first one I looked for was my own - not there!

However, when I called my phone from my house phone ... my contact entry came up!  Picture and everything! And when I clicked "View Contact Entry", it showed me the whole thing - perfectly! But I go back into the Contacts app ... not there!

This happens for a relatively small (but significant!) number of contacts that I could see so far - in other words, not just one ... at least 10 I counted.

I tried Settings->Apps->Media Storage->Clear Data and reboot ... clears the picture data, for sure, but not Contacts!

PLEASE somebody help me get sane again!  How can the contact be in the phone, but not show in Contacts?!  I can't find any specific way to rebuild the Contacts app's database - only to CLEAR DATA, which I don't want.

PLEASE ... help me get sane again:-)
From the surface clues, I thought the index was corrupt. Not the issue at all. Being a newbie to the Android, I was unaware of all the myriad features of the beast:-)

A lot more digging found the "problem". Namely, I use lots of category designations in my Outlook contacts. MyPhoneExplorer does a 100% correct job of transporting all these ... BUT, turns out the Android contacts app in its FILTER option treats these in a bizarre way. Namely, if you try ...

Contacts->->Filter->Display contacts->Local

... you see that ALL the existing categories are checked ... BUT, the very bottom one ("All other contacts") is NOT CHECKED. The result is that all contacts WITH categories get displayed, and any without a designated CATEGORY are NOT displayed.

Simple solution (discovered after a week of hell:-)) ... just check the "All other contacts" box, and PRESTO! Now I see everything.

Post-script: whoever designed this "Display contacts" feature has it backwards! The default should be to show ALL contacts, with option to the user to narrow the selection by UNCHECKING various boxes.