Time Machine/Time Capsule: What is the difference between "Waiting for index to be ready (100)" and "Waiting for index to be ready (101)"?
Solution 1:
The answer to your question is that the difference between these two codes (100 and 101) is not publicly documented by apple.
https://discussions.apple.com/message/23429422?ac_cid=op123456#23429422
However pondini.org/TM/D2.html gives reasons why and how to fix those errors, and the issues you are experiencing.