Metre2 Mail Pro
Send a quote, a chaser or a question, click the bell, and if nobody answers in the days you chose, Metre2 Mail tells you - with the email ready to follow up. A reply clears the reminder by itself, so you're only nudged about the ones that need it. Everything you're waiting on is in one place: Follow up. Part of Mail Pro.

Sheet 01Follow upNo reply yet
Writing an email, click the bell next to Send and choose when: 1, 2, 3 or 5 days, a week or two weeks. The composer says "Remind me if no reply in 3 days".
Open an email you sent and choose More > Remind me if no reply..., then pick a day and time.
A reply from any of the people you wrote to clears the reminder by itself. Emails waiting in the Outbox only start the clock when they really go.
When the time's up with no reply, a Windows notification says so and the email moves to No reply yet in Follow up, with a count on the left rail.
Write follow-up opens a reply to your own email, with everyone on it. Remind me later moves the reminder, and Done stops it.
Help: Writing email has every option in detail.
Part of Mail Pro. Metre2 Mail is free. Mail Pro is a one-off £9.99 upgrade inside the app, bought through the Microsoft Store - no subscription, no account. Try it free for 7 days.
It looks for a reply to your email - in the same conversation, from someone other than you, after you sent it - as mail arrives. When it finds one, the reminder goes.
No. Reminders are kept on your PC. Nothing is added to your email.
Follow-up reminders are part of Mail Pro, a one-off £9.99 upgrade with a free 7-day trial.
Your reminders are kept, quietly, until Pro is on again. Nothing is deleted.
Yes - open it in Sent and choose More > Remind me if no reply...

Work and school mail through Microsoft Graph - even where IMAP is switched off.

PST and OST files folder by folder, .mbox and .eml too - duplicates skipped.

Summaries free; reply drafts and translations with Pro - nothing leaves your PC.

Three free rules, and one right-click to make one. Unlimited with Pro.

Pin to the top with P, free. Colour-code with C in Mail Pro.

Blueprint paper in light, deep navy in dark - every email on clean paper.

Tracking pictures hidden, links cleaned, every email sandboxed, fakes flagged.

What, when, where and who - Accept, Tentative or Decline in one click. Free.

Every newsletter in one list: unsubscribe and tidy your inbox in one go. Mail Pro.
Metre2 Mail is free. Mail Pro is a one-off £9.99, with a free 7-day trial.