Installation

Three steps: VSTO installer, Claude Code CLI, OAuth sign-in. Total time about 5 minutes on a clean machine, 8 minutes on a corporate-managed one.

Requirements

Windows 10 (build 1809+) or Windows 11
Microsoft Excel 2016 or later (Office 365 desktop also fine)
WebView2 Evergreen runtime (already on every Windows 10 1903+ — if not, the installer prompts you)
~500 MB free disk space for HISAB + Claude Code binary
Internet connection (for AI calls + ERP connectors; the addin itself runs offline)

Step 1 — Install the VSTO add-in

Download HisabAddin.vsto from your account dashboard. Double-click it. Office prompts you to confirm the publisher (HISAB Labs); click Install. Takes ~30 seconds.

Per-user vs per-machine

The default installer is per-user — installs to %LOCALAPPDATA%\Apps\2.0 and doesn't require admin. If you're deploying across an org, use the per-machine MSI from the Enterprise dashboard; it goes to C:\Program Files\HISAB 360 and requires admin once.

Step 2 — Install Claude Code CLI

HISAB uses the Anthropic Claude Code CLI as the AI engine. It's a standalone signed binary (~227 MB) that you install once.

From the HISAB Settings panel, click Install Claude Code CLI. You'll see a one-line PowerShell command — copy it, run it in your own PowerShell (Win+R → powershell → paste → Enter). The installer downloads claude.exe to %APPDATA%\Claude\claude-code\<version>\.

When done, return to HISAB and click Done — Verify install.

EDR-friendly path (ReasonLabs, CrowdStrike, etc.)

Important: Some EDR products freeze any process spawned by Excel as a security precaution. If your laptop runs ReasonLabs, CrowdStrike, SentinelOne, or similar — even the in-app install button may hang silently.

HISAB's install flow is designed for this. You never click "Install" inside Excel; instead the panel shows you the install command and you run it yourself in a Win+R PowerShell. PowerShell launched by Win+R has explorer.exe as its parent — not Excel — so the EDR has no reason to gate it.

If you've installed Claude Code via the addin button and it appears to hang for more than 60 seconds, just close the PowerShell window the addin opened, open your own PowerShell with Win+R, and paste:

irm https://claude.ai/install.ps1 | iex

Then return to HISAB and click Done — Verify install. The addin will detect the freshly-installed binary and continue.

Step 3 — Sign in to Claude

After the verify step, the addin opens a second instruction card. Run this in PowerShell (it'll open your browser for OAuth):

claude /login

Sign in with your Anthropic account, accept the permissions, close the browser tab. Return to HISAB and click Done — Verify sign-in. HISAB checks for ~/.claude/.credentials.json to confirm.

Step 4 — Done

The HISAB MCP pill (top of the chat tab) flips from amber to green within a few seconds of your first chat message — that's the AI client successfully connecting to the local HISAB MCP server.

Uninstall

Standard Office add-in uninstall: Control Panel → Programs and Features, find "HISAB 360", click Uninstall. To also remove user data, delete %APPDATA%\HISAB\ after uninstalling.