User is trying to write a check for the first time, but cannot save it. User gets an error that a memo is required.
This happens if the project against which you are adding service or expense items in the check has the project rule Memo is required for time/expense entry active. These rules prevent you from saving time and expense entries without a memo. So you should remove these rules in the Projects > General > Assignment screen if you want to save the check without entering memos. To do so, select the rules and click on Actions > Delete. Check the Core Help for details on project rules.