Startup idea: Ghost Contact Cleaner for Microsoft 365
An MSP engineer spent three hours on why Exchange autocomplete suggests the real manager James plus a phantom James with a different surname, and there's no official fix.
Get the PRD prompt, $9.99 Market: $192K in 3 years
r/sysadmin · Sep 14, 2026 – Oct 14, 2026 · 102 upvotes
Unkillable ghost contacts created by AI in…
Read the thread · 34 comments
Ghost Contact Cleaner for Microsoft 365 is a startup idea for sysadmins and MSPs. An MSP engineer spent three hours on why Exchange autocomplete suggests the real manager James plus a phantom James with a different surname, and there's no official fix. A thread in r/sysadmin drew 102 upvotes and 34 comments between Sep 14, 2026 – Oct 14, 2026. People get by with PowerShell scripts, and that still leaves this job open. Hotness is 3.40, Warm. Real but moderate pain. Some willingness to pay. The thread drew 102 upvotes and 34 comments. No real solution exists. A 1-2 week mvp. A first version is a moderate amount of work, about 2 weeks, priced between $10 and $49 a month and charged as a B2B subscription. The pain, the source, the alternatives, the scope notes, and the questions on this page are free to read and free to build from. The agent starter prompt is the paid part. The first slice is on the page. One credit unlocks the rest, to paste into a coding agent, download as Markdown, or send as a private link.
Who has it
Sysadmins and MSPs.
What people use now
1 option, and the gap between them.
PowerShell scripts
No real solution exists yet.
Ghost Contact Cleaner for Microsoft 365 is built for the part these leave undone.
A way through
A niche tool for M365/Exchange admins that finds and safely removes 'ghost' contacts created by AI autocomplete features before they clutter the address book.
MVP scope
The first version, in 2 weeks.
- 00 Goal
The one job
Detect and safely remove AI-generated phantom contacts that pollute Exchange autocomplete.
- 01 Week 1
The core
Find the 'ghost' contacts that AI autocomplete creates in M365 and Exchange.
- 02 Week 1
The follow-through
Remove them safely before they clutter the address book.
- 03 Week 2
How it ships
As a web app that opens in any browser, with nothing to install. AI helps, but the core job works without it.
- — Not in v1
Left out on purpose
Replacing PowerShell scripts. Version one does the one job above and stops there.
How it could charge
The business model, at a glance.
- Model
- B2B SaaS
- Price
- $10–49 a month
- Buyer
- CompaniesA business with a budget pays
- Region
- Global
Hotness
Why it scores 3.40.
Real but moderate pain. Some willingness to pay. The thread drew 102 upvotes and 34 comments. No real solution exists. A 1-2 week mvp.
102 upvotes 34 comments r/sysadmin Sep 14, 2026 – Oct 14, 2026 verified Oct 14, 2026 Thread ↗
Weights: pain 25%, willingness to pay 20%, demand 20%, gap 15%, ease 10%, recency 10%. Recency is recomputed every build. The source report’s 1–10 score is not shown.
Market size · estimate
How big this could get
A bottom-up estimate for Ghost Contact Cleaner for Microsoft 365: real customer counts × a realistic price. Not a forecast.
$24M a year
40,000 MSPs · US managed service providers (est.)
$9.6M a year
16,000 MSPs · MSPs reachable through MSP communities
$192K a year
320 MSPs · 2% of the reachable segment in three years
What that means
320 MSPs at $50/mo = $192K ARR
Medium confidenceHow we estimated this
- Base: 40,000 US managed service providers (est.).
- Has the problem: 100% (nearly every MSP manages Microsoft 365 tenants).
- Revenue per MSP: $600 per year ($50/mo per MSP).
- Reachable: 40% (MSPs reachable through MSP communities).
- Three-year capture: 2% of the reachable segment.
TAM = customers with the problem × revenue per customer. SAM = the part an early product can reach. SOM = a conservative three-year share of SAM. Bars use a log scale. Shares marked “assume” are our judgment, not measured.
Source: CompTIA counts 100,000+ US solution providers and MSPs; we assume 40% run managed services
Take it to a build
Build Ghost Contact Cleaner for Microsoft 365 with an agent, or with us.
Agent starter prompt
$9.99 / 1 credit
A full PRD written for a coding agent: scope, data model, screens, edge cases, and the first week of tasks for this idea.
- Copy it straight into Claude Code, Cursor, or Codex.
- Download it as a .md file you keep.
- Send your bot a private link that refreshes every seven days.
# Agent starter prompt: Ghost Contact Cleaner for Microsoft 365 You are a senior product engineer. Build only the product described in this document. If a detail is missing, choose the smallest option and write it down in the README. Do not invent a second product, a marketplace of marketplaces, or a growth hack. ## Product Name: Ghost Contact Cleaner for Microsoft 365 One line: Detect and safely remove AI-generated phantom contacts that pollute Exchange autocomplete. Shape: Web app AI stance: AI-assisted Region for v1: Global Hotness (context only, not a requirement): 3.40 (warm). Real but moderate pain; some willingness to pay; thread engagement 102▲/34💬 (demand 2/5); no real solution exists; a 1-2 week mvp. ## Problem An MSP engineer spent three hours on why Exchange autocomplete suggests the real manager James plus a phantom James with a different surname, and there's no official fix. Who feels it: Sysadmins and MSPs.
The first slice is above. The rest unlocks for 1 credit and is never in this page’s HTML.
Credits work on both sites. On Business Ideas to Build the same credit unlocks the business plan and growth playbook for Ghost Contact Cleaner for Microsoft 365.
Or we build it
Your first version, shipped by our team.
A working product in your repo, built from this PRD. You own the code.
$1,000 scoping fee, credited toward the build.
Equity instead of cash is an application, not a checkout →Questions
Is this idea already taken?
People already use PowerShell scripts. Those options do not do the job in the solution above. The idea is free to build. Nothing here is an exclusive claim.
How hard is a first version?
Moderate. A tight MVP is about 2 weeks (2 weeks), assuming the regulated or partner-gated parts are stubbed. The paid prompt turns that into tasks.
Who would pay, and how?
The audience is sysadmins and MSPs. Charge a B2B subscription, and test a price between $10 and $49 a month. Willingness to pay is one input to Hotness, not a promise that someone will buy.
Can I use the evidence?
Yes. Build the product. The thread title is a short excerpt with a link, not a quote we are putting in someone's mouth. Exact post dates and verbatim lines are added only after a manual check. Ideas are suggestions, not medical, legal, or financial advice.
A business write-up of this idea, with its market size, sits on the sister site. The business-plan version