diff --git a/.github/workflows/smoke-test-basic-cache-provider.yml b/.github/workflows/smoke-test-basic-cache-provider.yml
index e32c811d..c31284b2 100644
--- a/.github/workflows/smoke-test-basic-cache-provider.yml
+++ b/.github/workflows/smoke-test-basic-cache-provider.yml
@@ -39,9 +39,12 @@ jobs:
       with:
         cache-provider: basic
         cache-read-only: false # For testing, allow writing cache entries on non-default branches
+    # Basic caching does no daemon management, so the workflow must ensure no daemon is left
+    # holding locks on the Gradle User Home when the post-action save runs. Without this, `tar`
+    # cannot read the Gradle '*.lock' files on Windows and the cache entry is never saved.
     - name: Build kotlin-dsl project
       working-directory: .github/workflow-samples/kotlin-dsl
-      run: ./gradlew build
+      run: ./gradlew build --no-daemon
 
   basic-cache-verify-build:
     needs: basic-cache-seed-build
diff --git a/sources/src/cache-service-basic.ts b/sources/src/cache-service-basic.ts
index 89a6350d..ad620b86 100644
--- a/sources/src/cache-service-basic.ts
+++ b/sources/src/cache-service-basic.ts
@@ -80,7 +80,28 @@ export class BasicCacheService implements CacheService {
         const cachePaths = getCachePaths(gradleUserHome)
 
         try {
-            await cache.saveCache(cachePaths, primaryKey)
+            // A cacheId of -1 means the save failed: `saveCache` reports the underlying cause and returns
+            // normally, rather than throwing. Warn and continue: caching failures should not fail the build.
+            const cacheId = await cache.saveCache(cachePaths, primaryKey)
+            if (cacheId === -1) {
+                core.warning(
+                    `Basic caching failed to save entry with key \`${primaryKey}\`. See preceding log output for the cause.`
+                )
+                return {
+                    status: 'enabled',
+                    entries: [
+                        entryReport({
+                            primaryKey,
+                            restoredKey,
+                            restoredOutcome: restoredKey
+                                ? '(Entry restored: exact match found)'
+                                : '(Entry not restored: no match found)',
+                            savedOutcome: '(Entry not saved: save failed)'
+                        })
+                    ]
+                }
+            }
+
             core.info(`Basic caching saved entry with key: ${primaryKey}`)
             return {
                 status: 'enabled',