OpenSlot · Help
Help
Most answers are below. If something billing-related looks wrong (charged twice, a seat not activating, a refund), email openslotadmin@gmail.com with the email address you signed in with — we answer those.
Getting started
How do I get a list of times everyone is free?
Sign in with your Microsoft 365 work account, add people (type a name to search your directory, or type an email and press Enter), choose a window and timezone, click Find free times. Copy, download, or — in Outlook — Insert straight into the email.
Why does my list say 08:00 AM – 05:00 PM all day?
Because nobody has anything on their calendar in that window. OpenSlot only removes times that are busy; free calendars produce full working days. Adjust Day starts / Day ends and Shortest slot to taste.
Nothing appears when I type a name.
The dropdown shows colleagues from your organization's directory. New tenants or brand-new hires can take a little while to index; typing the full email address and pressing Enter always works. Personal @outlook.com / @gmail accounts have no directory.
Someone's calendar was 'excluded' with a warning.
Their mailbox is outside your organization, or their free/busy is hidden by policy. Ask them (or IT) to share free/busy, or leave them out — the rest of the list is still correct.
Can I change the timezone of the list?
Yes — Timezone for the list. The list header always states which timezone it is in. Your timezone, hours and toggles are remembered on your account (people are not).
Signing in
It says 'Need admin approval'.
Your organization blocks employees from approving third-party apps. Send your IT admin the one-click consent link on Security & IT; after that, nobody in your company sees the prompt again.
Sign-in works but lookups fail.
Your account needs an Exchange Online mailbox (any Microsoft 365 Business/Enterprise seat). Personal Microsoft accounts can sign in but have no organization calendars to read.
I got signed out after a while.
Sessions refresh silently for as long as Microsoft allows; if your admin forces periodic re-authentication, just sign in again. Nothing is lost — your settings live on your account.
The Outlook add-in
How do I install it for myself?
Outlook → New mail → Apps (or Get add-ins) → search OpenSlot (once listed on AppSource), or install from file with the manifest at https://useopenslot.com/api/addin/manifest via aka.ms/olksideload → My add-ins → Add a custom add-in.
How does IT install it for everyone?
Microsoft 365 admin center → Settings → Integrated apps → Upload custom apps → Office add-in → link to the manifest above → choose users → Deploy. Details on Security & IT.
The button isn't showing after install.
Reload Outlook (close the compose window, press F5, or sign out/in). New installs can take 5–10 minutes to appear in the compose toolbar; look under Apps or the "…" overflow.
Insert put everything on one line.
Update to the latest version by closing and reopening the pane — current versions insert formatted HTML. Plain-text-format messages still get plain text.
Plans & billing
What do I get for free?
Every new account starts with 14 days of Pro (no card). After that, Free covers you + 1 person and a 7-day window, with a "Generated with OpenSlot" line on lists. Pro removes the limits and the line.
How much is Pro?
$7/user/month, or $72/year (that's $6/month — save $12 a year). Upgrade from the Upgrade / Keep Pro button; checkout is by Stripe (card, Apple/Google Pay, US bank debit).
How do Team seats work?
Click Buy team seats, pick a quantity (minimum 5; volume pricing applies automatically: 5–24 seats $5, 25–99 $4, 100+ $3 per user/month), then assign seats by email on /team. Colleagues get Pro instantly. Add or remove seats any time in Manage billing.
How do I change plan, update my card, get invoices, or cancel?
Manage billing (top right when signed in) opens the Stripe customer portal: switch monthly/yearly, change seats, update the card, download invoices, cancel at period end. No email needed.
My payment failed.
You keep access while Stripe retries the card over the next days and emails you a link to update it. If it ultimately fails, the account drops to Free; upgrading again restores Pro instantly.
Refunds?
Cancel any time and you keep access to the end of the paid period. If something is genuinely wrong (double charge, didn't get what you paid for), email openslotadmin@gmail.com and we'll sort it.
I paid but still see FREE.
Give it ~10 seconds and reload — activation arrives via Stripe's webhook. Still FREE after a minute? Email openslotadmin@gmail.com with your sign-in email.
Privacy
Read-only free/busy, fetched live, never stored. Details on Privacy and Security & IT.