Unfeigned means in email

"unfeigned" is a rather formal and old-fashioned word that means "genuine" or "sincere". In the context of an email, it could be used to express a genuine or sincere sentiment, such as:

• "I am writing to you unfeignedly to express my gratitude for your help."
• "I am unfeignedly sorry for the mistake I made in my previous email."

However, in modern email writing, it's more common to use simpler and more concise language to convey sincerity, such as:

• "Thank you sincerely for your help."
• "I apologize for the mistake. Please accept my apologies."

If you want to add a touch of formality to your email, you could use phrases like:

• "I am writing to express my heartfelt gratitude..."
• "I am truly sorry for the inconvenience..."

But in general, it's best to use language that is clear, concise, and easy to understand, rather than trying to use overly formal or old-fashioned words like "unfeigned".