Don't use any of these characters: * ? < > | " : \ / (asterisk, question mark, left and right-angle bracket, pipe, straight quotation marks, colon, BACKSLASH, FORWARD SLASH). Also, don't add the .qdf extension; Quicken does that for you.
After adding accounts, see if you are experiencing the same problems in this test file.
Mysteriously, downloads from NFCU are working again with no action on my part...Happens frequently with this institution
I am also having this issue with NFCU EVERY TIME Quicken updates!! I am now missing 2 months of transaction downloads that I am going to have to PRINT out the transactions from the bank and then MANUALLY verify each one to reconcile the account!