diff --git a/windows/README.md b/windows/README.md
index c4cfdc5..4cadb3c 100644
--- a/windows/README.md
+++ b/windows/README.md
@@ -182,6 +182,8 @@ winget install `
 
 The Store product ID `9PLM9XGG6VKS` is the ChatGPT Windows app managed here.
 ChatGPT Classic (`9NT1R1C2HH7J`) is intentionally not installed.
+WinGet's `APPINSTALLER_CLI_ERROR_UPDATE_NOT_APPLICABLE` result is treated as
+success because it means the installed ChatGPT version is already current.
 
 7-Zip is intentionally installed with its normal Windows installer through
 WinGet rather than as a portable Scoop package, because the normal installer
diff --git a/windows/applications/chatgpt/apply.ps1 b/windows/applications/chatgpt/apply.ps1
index a985a52..b329a94 100644
--- a/windows/applications/chatgpt/apply.ps1
+++ b/windows/applications/chatgpt/apply.ps1
@@ -8,6 +8,9 @@ winget install `
     --silent `
     --disable-interactivity
 
-if ($LASTEXITCODE -ne 0) {
-    throw "Failed to install or update ChatGPT."
+$exitCode = $LASTEXITCODE
+$updateNotApplicable = -1978335189 # 0x8A15002B
+
+if ($exitCode -notin @(0, $updateNotApplicable)) {
+    throw "Failed to install or update ChatGPT (WinGet exit code $exitCode)."
 }