I have had Windows 8, in which the search index used to complete then soon after its completion, it deletes and rebuilds itself!
I have then upgraded to Windows 10, the search index worked fine for few days, then it again stated to delete itself every few days. I.e. the search builds the index and finishes in couple of days, it says the indexing complete, then after few days it deletes itself and starts rebuilding the index again, again and so forth.
What could be the problem?