diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 486fded..b5cb384 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -13,11 +13,9 @@ jobs:
   test:
     name: default
     runs-on: windows-latest
-    strategy:
-      fail-fast: false
     steps:
       - name: Check out source code
-        uses: actions/checkout@v1
+        uses: actions/checkout@v2
       - name: Download Internet
         run: npm install
       - name: Enable Developer Command Prompt
@@ -32,6 +30,23 @@ jobs:
     runs-on: windows-latest
     steps:
       - name: Check out source code
-        uses: actions/checkout@v1
+        uses: actions/checkout@v2
       - run: npm install
       - run: npm audit --audit-level=moderate
+  alias-arch:
+    name: arch aliases
+    runs-on: windows-latest
+    steps:
+      - name: Check out source code
+        uses: actions/checkout@v2
+      - name: Download Internet
+        run: npm install
+      - name: Enable Developer Command Prompt
+        uses: ./
+        with:
+          arch: Win32
+      - name: Compile and run some C code
+        shell: cmd
+        run: |
+          cl.exe hello.c
+          hello.exe
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 03e739d..e9c853f 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -11,13 +11,11 @@ jobs:
   test:
     name: release
     runs-on: windows-latest
-    strategy:
-      fail-fast: false
     steps:
       - name: Setup Developer Command Prompt
         uses: ilammy/msvc-dev-cmd@v1
       - name: Check out source code
-        uses: actions/checkout@v1
+        uses: actions/checkout@v2
       - name: Compile and run some C code
         shell: cmd
         run: |
@@ -28,5 +26,5 @@ jobs:
     runs-on: windows-latest
     steps:
       - name: Check out source code
-        uses: actions/checkout@v1
+        uses: actions/checkout@v2
       - run: npm audit --audit-level=moderate
diff --git a/README.md b/README.md
index cd72800..71b3128 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,9 @@ Supports Windows. Does nothing on Linux and macOS.
 ## Inputs
 
 - `arch` – target architecture
-  - native compilation: `x86`, `x64` (default), `amd64` (synonym for x64)
+  - native compilation:
+    - `x64` (default) or its synonyms: `amd64`, `win64`
+    - `x86` or its synonyms: `win32`
   - cross-compilation: `x86_amd64`, `x86_arm`, `x86_arm64`,
   	`amd64_x86`, `amd64_arm`, `amd64_arm64`
 - `sdk` – Windows SDK to use
diff --git a/index.js b/index.js
index fec3981..a5a31a6 100644
--- a/index.js
+++ b/index.js
@@ -77,12 +77,23 @@ function main() {
     // Add standard location of "vswhere" to PATH, in case it's not there.
     process.env.PATH += path.delimiter + VSWHERE_PATH
 
-    const arch    = core.getInput('arch')
+    var   arch    = core.getInput('arch')
     const sdk     = core.getInput('sdk')
     const toolset = core.getInput('toolset')
     const uwp     = core.getInput('uwp')
     const spectre = core.getInput('spectre')
 
+    // There are all sorts of way the architectures are called. In addition to
+    // values supported by Microsoft Visual C++, recognize some common aliases.
+    let arch_aliases = {
+        "win32": "x86",
+        "win64": "x64",
+    }
+    // Ignore case when matching as that's what humans expect.
+    if (arch.toLowerCase() in arch_aliases) {
+        arch = arch_aliases[arch.toLowerCase()]
+    }
+
     // Due to the way Microsoft Visual C++ is configured, we have to resort to the following hack:
     // Call the configuration batch file and then output *all* the environment variables.
 
@@ -104,6 +115,24 @@ function main() {
     core.debug(`Running: ${command}`)
     const environment = child_process.execSync(command, {shell: "cmd"}).toString().split('\r\n')
 
+    // If vsvars.bat is given an incorrect command line, it will print out
+    // an error and *still* exit successfully. Parse out errors from output
+    // which don't look like environment variables, and fail if appropriate.
+    var failed = false
+    for (let line of environment) {
+        if (line.match(/^\[ERROR.*\]/)) {
+            failed = true
+            // Don't print this particular line which will be confusing in output.
+            if (line.match(/Error in script usage. The correct usage is:$/)) {
+                continue
+            }
+            core.error(line)
+        }
+    }
+    if (failed) {
+        throw new Error('invalid parameters')
+    }
+
     for (let string of environment) {
         const [name, value] = string.split('=')
         for (let pattern of InterestingVariables) {
diff --git a/package-lock.json b/package-lock.json
index ee228cc..e8c95d7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "msvc-dev-cmd",
-  "version": "1.5.0",
+  "version": "1.6.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index 549521d..5e14d1d 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "msvc-dev-cmd",
-  "version": "1.5.0",
+  "version": "1.6.0",
   "description": "GitHub Action to setup Developer Command Prompt for Microsoft Visual C++",
   "main": "index.js",
   "scripts": {