The Manage Transaction window shows these messages in a red box:

• Invalid date ! – the Date is empty.
• Invalid account ! – no valid entry chosen in Accounts.
• Invalid account currency ! – the chosen account has no currency (fix the account in the Chart of Accounts).
• Invalid transaction type 1!/2! – Type is not Deposit or Withdrawal.
• Invalid amount ! – Amount is empty.
• Invalid account category ! – no valid Category selected.
• Categorize first to mark as reviewed ! – you tried to review an uncategorized transaction.
• Invalid Transaction ! – the transaction you are editing no longer exists.
• Invalid Permissions ! – your role lacks Edit Accounting Transactions.