This has occurred 2 times since 1/24/2018. I posted the problem in April 2020 and it was suggested that syncing the checking register with a data set in the Quicken Cloud may breaking the transfer transaction. I found the identical error today with the same accounts. To summarize the issue: I write a check and and list the category which is the Asset account. Initially this links the transfer OK. This asset account is now inactive, but I did not delete it. I did hide it in the Account list. Not sure when this occurred but each time I discovered it was when I was doing a balance sheet report and it showed that account as having a balance. In the checks that paid off that account it gave a message as unknown account. I did not make any changes to the checks and there were only 2 going into this account.
