diff --git a/README.md b/README.md
index 3923413..86b46b9 100644
--- a/README.md
+++ b/README.md
@@ -145,7 +145,9 @@ sudo scripts/install-extension-policy.sh
 ```
 
 No administrator rights on Windows, where it goes into the user's own policy
-hive; root on Linux, where Chrome only reads policy from `/etc`. See
+hive; root on Linux, where Chrome only reads policy from `/etc`. **Not Edge** —
+an unmanaged Edge refuses to install anything that is not from the Microsoft
+Store, so use Chrome or Brave, or run the unpacked copy there. See
 [deploy/README.md](deploy/README.md). Either way the extension notices when
 the dashboard is running newer code than it is: a policy install asks Chrome to
 fetch the new CRX, an unpacked one reloads itself from disk. Clicking the reload
diff --git a/deploy/README.md b/deploy/README.md
index 49189fc..eb465b9 100644
--- a/deploy/README.md
+++ b/deploy/README.md
@@ -93,10 +93,22 @@ powershell -NoProfile -ExecutionPolicy Bypass -File scripts\install-extension-po
 sudo scripts/install-extension-policy.sh
 ```
 
-Both configure every Chromium-family browser they find — Chrome, Edge and Brave
-take the same CRX, the same update manifest and the same policy, differing only
-in where that policy is written. Narrow it with `-Browser Edge` if you would
-rather not.
+Both configure every Chromium-family browser they find, and narrowing that to
+one is `-Browser Chrome`.
+
+**Edge is the exception, and it is not one we can fix.** Unmanaged Edge installs
+extensions from the Microsoft Store and nowhere else. It reads the policy and
+then blanks it — `edge://policy` shows `[BLOCKED]<id>;<url>` with "This device
+isn't managed by your organization" — so a self-hosted CRX cannot be installed
+there at all unless the machine is domain-joined, Intune-enrolled or
+Entra-joined. Chrome and Brave have no equivalent restriction. The script
+detects this and skips Edge rather than leaving a permanent policy error and a
+"Managed by your organization" badge behind; `-Force` overrides it.
+
+On a machine that has to be Edge, load `extension/` unpacked there instead. It
+still picks up releases: an unpacked copy reloads itself from disk when the
+dashboard reports a newer version, which is what the updater has already
+pulled.
 
 The Windows script writes to the current user's policy hive and needs no
 elevation; `-Scope Machine` covers every account on the box and does need an
diff --git a/scripts/install-extension-policy.ps1 b/scripts/install-extension-policy.ps1
index a8b9023..9ff58f9 100644
--- a/scripts/install-extension-policy.ps1
+++ b/scripts/install-extension-policy.ps1
@@ -44,7 +44,10 @@ param(
 
     [string]$UpdateUrl = 'https://ext.juicerroom.com/updates.xml',
 
-    [switch]$Remove
+    [switch]$Remove,
+
+    # Write the Edge policy even though Edge will refuse to act on it.
+    [switch]$Force
 )
 
 $ErrorActionPreference = 'Stop'
@@ -91,6 +94,28 @@ function Test-BrowserInstalled([string]$Name) {
     return $false
 }
 
+<#
+    Edge refuses to install an extension it did not get from the Microsoft Store
+    unless the device is managed — domain-joined, Intune-enrolled or Entra-joined.
+    The policy is read and then blanked: edge://policy shows the value as
+    "[BLOCKED]..." with "This device isn't managed by your organization", and an
+    "Invalid extension ID" error from parsing that prefix.
+
+    Chrome and Brave have no such restriction. So on an unmanaged machine there
+    is nothing to be gained by writing Edge's key, and a real cost: Edge starts
+    reporting "Managed by your organization" and shows a policy error forever.
+#>
+function Test-DeviceManaged {
+    try {
+        $status = & dsregcmd /status 2>$null | Out-String
+        return ($status -match 'AzureAdJoined\s*:\s*YES') -or
+               ($status -match 'DomainJoined\s*:\s*YES') -or
+               ($status -match 'EnterpriseJoined\s*:\s*YES')
+    } catch {
+        return $false      # no dsregcmd is itself a fair sign this is not managed
+    }
+}
+
 $hive = if ($Scope -eq 'Machine') { 'HKLM:' } else { 'HKCU:' }
 
 if ($Scope -eq 'Machine') {
@@ -111,6 +136,20 @@ if (-not $targets) {
     throw 'Found no Chrome, Edge or Brave installation. Name one with -Browser to configure it regardless of what this can see.'
 }
 
+if (-not $Remove -and ($targets -contains 'Edge') -and -not $Force -and -not (Test-DeviceManaged)) {
+    Write-Warning @'
+Edge is skipped: this device is not managed (not domain-joined, Intune-enrolled
+or Entra-joined), and unmanaged Edge only installs extensions from the Microsoft
+Store. It would read the policy and blank the value.
+
+  Use Chrome or Brave for the update-server install, or load extension\ unpacked
+  in Edge - an unpacked copy still reloads itself when the dashboard reports a
+  newer version. -Force writes the key anyway.
+'@
+    $targets = @($targets | Where-Object { $_ -ne 'Edge' })
+    if (-not $targets) { exit 1 }
+}
+
 Write-Host "Configuring: $($targets -join ', ')"