[Removed-Speculation]... Here's the deal:
I don't need to know how to troubleshoot this. I am able to generate a comparison file to identify the transactions that were there on my last back-up and compare them to my current register.
The trouble is -- that seems to coincide with the end of a calendar month and/or a Quicken Update -- when the system comes back, it drops transactions. This time it was 1 in the checking account; 3 in the savings account. So the trouble is shot!
The other aspects I noticed this time is 1) the transactions were relatively recent (the last 2 weeks); 2) They were transfers between the bank accounts and my MasterCard.
So...it may have to do with the relationship between Quicken and the bank -- but it is still Quicken's problem! Please! Work with the banking community to fix the problem. This is a service that we subscribers pay for. Make it worth the cost.
[Edited-Readability]