diff --git a/src/server/editorServices.ts b/src/server/editorServices.ts
index 624360c4fc7e0..02c5ccb08970e 100644
--- a/src/server/editorServices.ts
+++ b/src/server/editorServices.ts
@@ -66,6 +66,7 @@ import {
     IncompleteCompletionsCache,
     IndentStyle,
     isArray,
+    isExternalModuleNameRelative,
     isIgnoredFileFromWildCardWatching,
     isInsideNodeModules,
     isJsonEqual,
@@ -89,7 +90,6 @@ import {
     ParsedCommandLine,
     parseJsonSourceFileConfigFileContent,
     parseJsonText,
-    parsePackageName,
     Path,
     PerformanceEvent,
     PluginImport,
@@ -4487,7 +4487,11 @@ export class ProjectService {
         }
 
         this.logger.info(`Enabling plugin ${pluginConfigEntry.name} from candidate paths: ${searchPaths.join(",")}`);
-        if (!pluginConfigEntry.name || parsePackageName(pluginConfigEntry.name).rest) {
+        if (
+            !pluginConfigEntry.name ||
+            isExternalModuleNameRelative(pluginConfigEntry.name) ||
+            /[\\/]\.\.?($|[\\/])/.test(pluginConfigEntry.name)
+        ) {
             this.logger.info(`Skipped loading plugin ${pluginConfigEntry.name || JSON.stringify(pluginConfigEntry)} because only package name is allowed plugin name`);
             return;
         }
diff --git a/src/testRunner/unittests/tsserver/plugins.ts b/src/testRunner/unittests/tsserver/plugins.ts
index f984abc93774f..3a6f755f86021 100644
--- a/src/testRunner/unittests/tsserver/plugins.ts
+++ b/src/testRunner/unittests/tsserver/plugins.ts
@@ -45,8 +45,20 @@ describe("unittests:: tsserver:: plugins:: loading", () => {
     }
 
     it("With local plugins", () => {
-        const expectedToLoad = ["@myscoped/plugin", "unscopedPlugin"];
-        const notToLoad = ["../myPlugin", "myPlugin/../malicious"];
+        const expectedToLoad = [
+            "@myscoped/plugin",
+            "@myscoped/plugin/subpath",
+            "@myscoped/plugin/sub/path",
+            "unscopedPlugin",
+            "unscopedPlugin/subpath",
+            "unscopedPlugin/sub/path",
+        ];
+        const notToLoad = [
+            "../myPlugin",
+            "@myscoped/plugin/../malicious",
+            "myPlugin/../malicious",
+            "myPlugin/subpath/../../malicious",
+        ];
         const aTs: File = { path: "/a.ts", content: `class c { prop = "hello"; foo() { return this.prop; } }` };
         const tsconfig: File = {
             path: "/tsconfig.json",
@@ -65,8 +77,20 @@ describe("unittests:: tsserver:: plugins:: loading", () => {
     });
 
     it("With global plugins", () => {
-        const expectedToLoad = ["@myscoped/plugin", "unscopedPlugin"];
-        const notToLoad = ["../myPlugin", "myPlugin/../malicious"];
+        const expectedToLoad = [
+            "@myscoped/plugin",
+            "@myscoped/plugin/subpath",
+            "@myscoped/plugin/sub/path",
+            "unscopedPlugin",
+            "unscopedPlugin/subpath",
+            "unscopedPlugin/sub/path",
+        ];
+        const notToLoad = [
+            "../myPlugin",
+            "@myscoped/plugin/../malicious",
+            "myPlugin/../malicious",
+            "myPlugin/subpath/../../malicious",
+        ];
         const aTs: File = { path: "/a.ts", content: `class c { prop = "hello"; foo() { return this.prop; } }` };
         const tsconfig: File = {
             path: "/tsconfig.json",
diff --git a/tests/baselines/reference/tsserver/plugins/With-global-plugins.js b/tests/baselines/reference/tsserver/plugins/With-global-plugins.js
index f170d952d37d6..f3027f9236829 100644
--- a/tests/baselines/reference/tsserver/plugins/With-global-plugins.js
+++ b/tests/baselines/reference/tsserver/plugins/With-global-plugins.js
@@ -60,17 +60,43 @@ Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin from candidate paths:
 Info seq  [hh:mm:ss:mss] Loading @myscoped/plugin from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
 Loading plugin: @myscoped/plugin
 Info seq  [hh:mm:ss:mss] Plugin validation succeeded
+Info seq  [hh:mm:ss:mss] Loading global plugin @myscoped/plugin/subpath
+Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin/subpath from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading @myscoped/plugin/subpath from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: @myscoped/plugin/subpath
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
+Info seq  [hh:mm:ss:mss] Loading global plugin @myscoped/plugin/sub/path
+Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin/sub/path from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading @myscoped/plugin/sub/path from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: @myscoped/plugin/sub/path
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
 Info seq  [hh:mm:ss:mss] Loading global plugin unscopedPlugin
 Info seq  [hh:mm:ss:mss] Enabling plugin unscopedPlugin from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Loading unscopedPlugin from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
 Loading plugin: unscopedPlugin
 Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
+Info seq  [hh:mm:ss:mss] Loading global plugin unscopedPlugin/subpath
+Info seq  [hh:mm:ss:mss] Enabling plugin unscopedPlugin/subpath from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading unscopedPlugin/subpath from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: unscopedPlugin/subpath
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
+Info seq  [hh:mm:ss:mss] Loading global plugin unscopedPlugin/sub/path
+Info seq  [hh:mm:ss:mss] Enabling plugin unscopedPlugin/sub/path from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading unscopedPlugin/sub/path from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: unscopedPlugin/sub/path
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
 Info seq  [hh:mm:ss:mss] Loading global plugin ../myPlugin
 Info seq  [hh:mm:ss:mss] Enabling plugin ../myPlugin from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Skipped loading plugin ../myPlugin because only package name is allowed plugin name
+Info seq  [hh:mm:ss:mss] Loading global plugin @myscoped/plugin/../malicious
+Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin/../malicious from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Skipped loading plugin @myscoped/plugin/../malicious because only package name is allowed plugin name
 Info seq  [hh:mm:ss:mss] Loading global plugin myPlugin/../malicious
 Info seq  [hh:mm:ss:mss] Enabling plugin myPlugin/../malicious from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Skipped loading plugin myPlugin/../malicious because only package name is allowed plugin name
+Info seq  [hh:mm:ss:mss] Loading global plugin myPlugin/subpath/../../malicious
+Info seq  [hh:mm:ss:mss] Enabling plugin myPlugin/subpath/../../malicious from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Skipped loading plugin myPlugin/subpath/../../malicious because only package name is allowed plugin name
 Info seq  [hh:mm:ss:mss] FileWatcher:: Added:: WatchInfo: /a/lib/lib.d.ts 500 undefined WatchType: Closed Script info
 Info seq  [hh:mm:ss:mss] Starting updateGraphWorker: Project: /tsconfig.json
 Info seq  [hh:mm:ss:mss] Finishing updateGraphWorker: Project: /tsconfig.json Version: 1 structureChanged: true structureIsReused:: Not Elapsed:: *ms
diff --git a/tests/baselines/reference/tsserver/plugins/With-local-plugins.js b/tests/baselines/reference/tsserver/plugins/With-local-plugins.js
index 65cf96c9cef6b..206bfa2a917be 100644
--- a/tests/baselines/reference/tsserver/plugins/With-local-plugins.js
+++ b/tests/baselines/reference/tsserver/plugins/With-local-plugins.js
@@ -11,15 +11,33 @@ class c { prop = "hello"; foo() { return this.prop; } }
       {
         "name": "@myscoped/plugin"
       },
+      {
+        "name": "@myscoped/plugin/subpath"
+      },
+      {
+        "name": "@myscoped/plugin/sub/path"
+      },
       {
         "name": "unscopedPlugin"
       },
+      {
+        "name": "unscopedPlugin/subpath"
+      },
+      {
+        "name": "unscopedPlugin/sub/path"
+      },
       {
         "name": "../myPlugin"
       },
+      {
+        "name": "@myscoped/plugin/../malicious"
+      },
       {
         "name": "myPlugin/../malicious"
       },
+      {
+        "name": "myPlugin/subpath/../../malicious"
+      },
       {
         "transform": "some-transform"
       }
@@ -74,15 +92,33 @@ Info seq  [hh:mm:ss:mss] Config: /tsconfig.json : {
    {
     "name": "@myscoped/plugin"
    },
+   {
+    "name": "@myscoped/plugin/subpath"
+   },
+   {
+    "name": "@myscoped/plugin/sub/path"
+   },
    {
     "name": "unscopedPlugin"
    },
+   {
+    "name": "unscopedPlugin/subpath"
+   },
+   {
+    "name": "unscopedPlugin/sub/path"
+   },
    {
     "name": "../myPlugin"
    },
+   {
+    "name": "@myscoped/plugin/../malicious"
+   },
    {
     "name": "myPlugin/../malicious"
    },
+   {
+    "name": "myPlugin/subpath/../../malicious"
+   },
    {
     "transform": "some-transform"
    }
@@ -96,14 +132,34 @@ Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin from candidate paths:
 Info seq  [hh:mm:ss:mss] Loading @myscoped/plugin from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
 Loading plugin: @myscoped/plugin
 Info seq  [hh:mm:ss:mss] Plugin validation succeeded
+Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin/subpath from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading @myscoped/plugin/subpath from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: @myscoped/plugin/subpath
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
+Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin/sub/path from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading @myscoped/plugin/sub/path from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: @myscoped/plugin/sub/path
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
 Info seq  [hh:mm:ss:mss] Enabling plugin unscopedPlugin from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Loading unscopedPlugin from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
 Loading plugin: unscopedPlugin
 Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
+Info seq  [hh:mm:ss:mss] Enabling plugin unscopedPlugin/subpath from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading unscopedPlugin/subpath from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: unscopedPlugin/subpath
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
+Info seq  [hh:mm:ss:mss] Enabling plugin unscopedPlugin/sub/path from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Loading unscopedPlugin/sub/path from /a/lib/tsc.js/../../.. (resolved to /a/lib/tsc.js/../../../node_modules)
+Loading plugin: unscopedPlugin/sub/path
+Info seq  [hh:mm:ss:mss] Plugin activation failed: Error: Protocol handler already exists for command "testProtocolCommand"
 Info seq  [hh:mm:ss:mss] Enabling plugin ../myPlugin from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Skipped loading plugin ../myPlugin because only package name is allowed plugin name
+Info seq  [hh:mm:ss:mss] Enabling plugin @myscoped/plugin/../malicious from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Skipped loading plugin @myscoped/plugin/../malicious because only package name is allowed plugin name
 Info seq  [hh:mm:ss:mss] Enabling plugin myPlugin/../malicious from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Skipped loading plugin myPlugin/../malicious because only package name is allowed plugin name
+Info seq  [hh:mm:ss:mss] Enabling plugin myPlugin/subpath/../../malicious from candidate paths: /a/lib/tsc.js/../../..
+Info seq  [hh:mm:ss:mss] Skipped loading plugin myPlugin/subpath/../../malicious because only package name is allowed plugin name
 Info seq  [hh:mm:ss:mss] Enabling plugin undefined from candidate paths: /a/lib/tsc.js/../../..
 Info seq  [hh:mm:ss:mss] Skipped loading plugin {"transform":"some-transform"} because only package name is allowed plugin name
 Info seq  [hh:mm:ss:mss] FileWatcher:: Added:: WatchInfo: /a/lib/lib.d.ts 500 undefined WatchType: Closed Script info
@@ -155,6 +211,12 @@ Info seq  [hh:mm:ss:mss] event:
           },
           "compilerOptions": {
             "plugins": [
+              "",
+              "",
+              "",
+              "",
+              "",
+              "",
               "",
               "",
               "",