diff --git a/src/server/typingsInstaller/nodeTypingsInstaller.ts b/src/server/typingsInstaller/nodeTypingsInstaller.ts
index 378708a4a81..36f5adab400 100644
--- a/src/server/typingsInstaller/nodeTypingsInstaller.ts
+++ b/src/server/typingsInstaller/nodeTypingsInstaller.ts
@@ -185,7 +185,7 @@ namespace ts.server.typingsInstaller {
             if (this.log.isEnabled()) {
                 this.log.writeLine(`#${requestId} with arguments'${JSON.stringify(packageNames)}'.`);
             }
-            const command = `${this.npmPath} install@latest --ignore-scripts ${packageNames.join(" ")} --save-dev --force --user-agent="typesInstaller/${version}"`;
+            const command = `${this.npmPath} install --ignore-scripts ${packageNames.join(" ")} --save-dev --user-agent="typesInstaller/${version}"`;
             const start = Date.now();
             const hasError = this.execSyncAndLog(command, { cwd });
             if (this.log.isEnabled()) {
diff --git a/src/server/typingsInstaller/typingsInstaller.ts b/src/server/typingsInstaller/typingsInstaller.ts
index 22982b60075..cf441017de9 100644
--- a/src/server/typingsInstaller/typingsInstaller.ts
+++ b/src/server/typingsInstaller/typingsInstaller.ts
@@ -19,6 +19,8 @@ namespace ts.server.typingsInstaller {
         writeLine: noop
     };
 
+    const timestampsFile = "timestamps.json";
+
     function typingToFileName(cachePath: string, packageName: string, installTypingHost: InstallTypingHost, log: Log): string {
         try {
             const result = resolveModuleName(packageName, combinePaths(cachePath, "index.d.ts"), { moduleResolution: ModuleResolutionKind.NodeJs }, installTypingHost);
@@ -223,7 +225,7 @@ namespace ts.server.typingsInstaller {
                 }
                 return;
             }
-            const timestampJson = combinePaths(cacheLocation, "timestamps.json");
+            const timestampJson = combinePaths(cacheLocation, timestampsFile);
             this.typeDeclarationTimestamps = loadTypeDeclarationTimestampFile(timestampJson, this.installTypingHost, this.log);
             const packageJson = combinePaths(cacheLocation, "package.json");
             if (this.log.isEnabled()) {
@@ -264,6 +266,9 @@ namespace ts.server.typingsInstaller {
                             // defaults to old behavior of never updating if we ever use a host without getModifiedTime in the future
                             const timestamp = this.installTypingHost.getModifiedTime === undefined ? Date.now() : this.installTypingHost.getModifiedTime(typingFile).getTime();
                             this.typeDeclarationTimestamps[key] = timestamp;
+                            if (this.log.isEnabled()) {
+                                this.log.writeLine(`Adding entry into timestamp cache: '${key}' => '${timestamp}'`);
+                            }
                         }
                         // timestamp guaranteed to not be undefined by above check
                         const newTyping: JsTyping.CachedTyping = { typingLocation: typingFile, timestamp: getProperty(this.typeDeclarationTimestamps, key) };
@@ -360,6 +365,7 @@ namespace ts.server.typingsInstaller {
                         this.log.writeLine(`Installed typings ${JSON.stringify(scopedTypings)}`);
                     }
                     const installedTypingFiles: string[] = [];
+                    const typesPackageName = (packageName: string) => `@types/${packageName}`;
                     for (const packageName of filteredTypings) {
                         const typingFile = typingToFileName(cachePath, packageName, this.installTypingHost, this.log);
                         if (!typingFile) {
@@ -370,7 +376,7 @@ namespace ts.server.typingsInstaller {
                         const newTimestamp = Date.now();
                         const newTyping: JsTyping.CachedTyping = { typingLocation: typingFile, timestamp: newTimestamp };
                         this.packageNameToTypingLocation.set(packageName, newTyping);
-                        this.typeDeclarationTimestamps[packageName] = newTimestamp;
+                        this.typeDeclarationTimestamps[typesPackageName(packageName)] = newTimestamp;
                         installedTypingFiles.push(typingFile);
                     }
                     if (this.log.isEnabled()) {
@@ -378,7 +384,8 @@ namespace ts.server.typingsInstaller {
                     }
 
                     const newFileContents: TypeDeclarationTimestampFile = { entries: this.typeDeclarationTimestamps };
-                    writeTypeDeclarationTimestampFile(cachePath, newFileContents, this.installTypingHost, this.log); // WRONG PATH
+                    const timestampJson = combinePaths(cachePath, timestampsFile);
+                    writeTypeDeclarationTimestampFile(timestampJson, newFileContents, this.installTypingHost, this.log);
 
                     this.sendResponse(this.createSetTypings(req, currentlyCachedTypings.concat(installedTypingFiles)));
                 }
diff --git a/src/services/jsTyping.ts b/src/services/jsTyping.ts
index 85660a03368..b26b2a00a84 100644
--- a/src/services/jsTyping.ts
+++ b/src/services/jsTyping.ts
@@ -31,10 +31,16 @@ namespace ts.JsTyping {
         timestamp: number;
     }
 
-    const typingLifetime = new Date(0, 1);
-
     export function isTypingExpired(typing: JsTyping.CachedTyping | undefined) {
-        return typing && Date.now() - typingLifetime.getTime() < typing.timestamp;
+        const comparisonDate = new Date();
+        const currentMonth = comparisonDate.getMonth();
+        if (currentMonth) {
+            comparisonDate.setMonth(11);
+            comparisonDate.setFullYear(comparisonDate.getFullYear() - 1);
+        } else {
+            comparisonDate.setMonth(currentMonth - 1);
+        }
+        return !typing || typing.timestamp < comparisonDate.getTime();
     }
 
     /* @internal */