Installation

Two steps for most people: run the signed installer (the Claude Code and Codex AI engines are set up automatically), then sign in to HISAB in Excel — the built-in HISAB AI works right away. Using your own AI account instead? One extra step: sign in to it. About 5 minutes on a clean machine, a little longer on a corporate-managed one.

Full installation walkthrough — about 3 minutes, start to finish. See the full walkthrough: Install the HISAB 360 Excel add-in on Windows.

Requirements

Windows 10 (build 1809+) or Windows 11
Microsoft Excel 2016 or later, or Microsoft 365 desktop (the desktop app, not Excel for the web)
.NET Framework 4.8 (already on current Windows 10/11)
WebView2 Evergreen runtime (already on every Windows 10 1903+ — if not, the installer pulls it in)
Node.js is bundled with HISAB — there is nothing separate to download
Internet connection (for AI calls + ERP connectors; the add-in itself runs offline)

Step 1 — Download and run the HISAB installer

Get the signed installer from the Download page — click Download for Windows (it serves the right build for your Office bitness) — or from your account dashboard. You'll get HISAB-360-Setup-64bit.exe (or HISAB-360-Setup-32bit.exe if your Office is 32-bit), accompanied by an MSI for IT deployment. It is Authenticode code-signed with the publisher's own certificate.

Run the downloaded file. Because the certificate is still building reputation, Windows SmartScreen may warn "Windows protected your PC." — click More info → Run anyway to continue (this is expected for a newly signed installer). Approve the one-time admin (UAC) prompt, then follow the setup wizard through to the end.

The installer is per-machine — it installs to C:\Program Files\HISAB. This is a real signed setup, not a .vsto double-click and not a per-user ClickOnce install under %LOCALAPPDATA%\Apps\2.0. Launch Excel afterward and the HISAB panel appears in the ribbon.

Step 2 — Open Excel and sign in to HISAB

Launch Excel and open a workbook — the HISAB 360 panel appears. If Excel asks you to enable the add-in, allow it. Open the panel and sign in to HISAB with the same account you used on the website (Google, GitHub, or email) to activate your free 15-day trial. You can check your plan and trial status any time on your account dashboard.

Step 3 — Choose your AI: built-in HISAB AI, or your own account

HISAB gives you two AI modes, switchable any time with the AI source toggle in Settings:

HISAB AI (built in, zero setup) — works the moment you sign in to HISAB. Pick a model and chat; usage is metered in simple credits, and your trial includes 50 free credits. Nothing to install, no other accounts to create. If this is you, you're done — skip straight to "Verify and connect".
Own AI (your Anthropic or OpenAI account) — HISAB drives your own AI through a local MCP server, and usage is billed to you by Anthropic or OpenAI at their rates, with no markup. The Claude Code and Codex engines were already installed automatically when HISAB installed — there are no commands to run. Pick whichever you prefer and flip between them with the provider toggle.

If an engine is ever missing (self-heal). On rare corporate-managed machines, endpoint-security / EDR products (ReasonLabs, CrowdStrike, SentinelOne and similar) can block the automatic engine setup. The Install Claude / Install Codex card in Settings covers this: it shows a one-line command with a Copy button that you run in your own terminal (npm install -g @anthropic-ai/claude-code or npm install -g @openai/codex — Node.js is bundled, so npm just works). Running it from your own shell is deliberate and EDR-safe: the process is parented by your shell, not EXCEL.EXE, so endpoint security doesn't gate it. Then click Verify — detection is restart-free.

Step 4 — Own AI only: sign in with your AI account

Using HISAB AI? Skip this step.

On the sign-in card, click Sign in for your engine — HISAB opens your browser to authenticate. Don't hand-type a bare login command: the button (and its Copy command) builds the exact line for your machine, because each engine needs a little setup first —

Claude: the button adds Claude's install folder to your PATH (it isn't on PATH in a terminal you opened before installing), then signs you in through your browser.
Codex: the button runs set CODEX_HOME=%APPDATA%\HISAB\codex-home && codex login, so the sign-in lands in HISAB's isolated Codex home — a bare codex login writes elsewhere and HISAB won't detect it.

Your browser opens directly on the provider's authorization page. Approve the access — with a subscription (a Claude or ChatGPT plan — recommended, far more usage per dollar) or a pay-as-you-go API key — and the sign-in completes automatically; there is no code to copy or paste. Return to HISAB and click Verify.

Browser didn't open? Click Sign in again, or use the card's Copy command button to run the same login from a terminal — it re-opens the browser and authorizes automatically.

Verify and connect

Send a quick message like hi. On HISAB AI a reply simply comes back — you're done. On Own AI, pick your model first (for Claude, Claude Opus is a great default); the MCP pill at the top of the Chat tab goes from amber to green ("MCP connected") as the reply arrives — that's your AI client talking to the local HISAB MCP server, end to end. Verification is restart-free — after each Verify click, HISAB re-checks on the spot.

Uninstall

Remove HISAB from Settings → Apps (or Control Panel → Programs and Features) — find "HISAB 360" and click Uninstall. The uninstaller removes only what HISAB installed: the %APPDATA% / %LOCALAPPDATA% HISAB folders, its HKCU registry entries, the PATH entries it added, the HISAB MCP entries it wrote into the AI CLIs' configs, and — if HISAB installed the Claude Code engine for you — that engine's program files. Your data is never touched: a Claude/Codex install you had before HISAB is left alone, and your AI sign-in, settings and chat history are always preserved.