diff --git a/src/jsTyping/jsTyping.ts b/src/jsTyping/jsTyping.ts
index a573536255a81..db699d5b32c5e 100644
--- a/src/jsTyping/jsTyping.ts
+++ b/src/jsTyping/jsTyping.ts
@@ -327,7 +327,8 @@ export const enum NameValidationResult {
     NameTooLong,
     NameStartsWithDot,
     NameStartsWithUnderscore,
-    NameContainsNonURISafeCharacters,
+    NameContainsInvalidCharacters,
+    NameContainsNonURISafeCharacters = NameContainsInvalidCharacters, // for backward compatibility
 }
 
 const maxPackageNameLength = 214;
@@ -381,8 +382,8 @@ function validatePackageNameWorker(packageName: string, supportScopedPackage: bo
             return NameValidationResult.Ok;
         }
     }
-    if (encodeURIComponent(packageName) !== packageName) {
-        return NameValidationResult.NameContainsNonURISafeCharacters;
+    if (!/^[\w.-]+$/.test(packageName)) {
+        return NameValidationResult.NameContainsInvalidCharacters;
     }
     return NameValidationResult.Ok;
 }
@@ -405,8 +406,8 @@ function renderPackageNameValidationFailureWorker(typing: string, result: NameVa
             return `'${typing}':: ${kind} name '${name}' cannot start with '.'`;
         case NameValidationResult.NameStartsWithUnderscore:
             return `'${typing}':: ${kind} name '${name}' cannot start with '_'`;
-        case NameValidationResult.NameContainsNonURISafeCharacters:
-            return `'${typing}':: ${kind} name '${name}' contains non URI safe characters`;
+        case NameValidationResult.NameContainsInvalidCharacters:
+            return `'${typing}':: ${kind} name '${name}' contains invalid characters`;
         case NameValidationResult.Ok:
             return Debug.fail(); // Shouldn't have called this.
         default:
diff --git a/src/testRunner/unittests/tsserver/typingsInstaller.ts b/src/testRunner/unittests/tsserver/typingsInstaller.ts
index 1c7e77ae4039f..a832f3f2fcfe6 100644
--- a/src/testRunner/unittests/tsserver/typingsInstaller.ts
+++ b/src/testRunner/unittests/tsserver/typingsInstaller.ts
@@ -1524,10 +1524,11 @@ describe("unittests:: tsserver:: typingsInstaller:: Validate package name:", ()
     it("package name cannot start with underscore", () => {
         assert.equal(validatePackageName("_foo"), NameValidationResult.NameStartsWithUnderscore);
     });
-    it("package non URI safe characters are not supported", () => {
-        assert.equal(validatePackageName("  scope  "), NameValidationResult.NameContainsNonURISafeCharacters);
-        assert.equal(validatePackageName("; say ‘Hello from TypeScript!’ #"), NameValidationResult.NameContainsNonURISafeCharacters);
-        assert.equal(validatePackageName("a/b/c"), NameValidationResult.NameContainsNonURISafeCharacters);
+    it("package invalid characters are not supported", () => {
+        assert.equal(validatePackageName("  scope  "), NameValidationResult.NameContainsInvalidCharacters);
+        assert.equal(validatePackageName("; say ‘Hello from TypeScript!’ #"), NameValidationResult.NameContainsInvalidCharacters);
+        assert.equal(validatePackageName("a/b/c"), NameValidationResult.NameContainsInvalidCharacters);
+        assert.equal(validatePackageName("react'test"), NameValidationResult.NameContainsInvalidCharacters);
     });
     it("scoped package name is supported", () => {
         assert.equal(validatePackageName("@scope/bar"), NameValidationResult.Ok);
@@ -1540,10 +1541,10 @@ describe("unittests:: tsserver:: typingsInstaller:: Validate package name:", ()
         assert.deepEqual(validatePackageName("@_scope/bar"), { name: "_scope", isScopeName: true, result: NameValidationResult.NameStartsWithUnderscore });
         assert.deepEqual(validatePackageName("@_scope/_bar"), { name: "_scope", isScopeName: true, result: NameValidationResult.NameStartsWithUnderscore });
     });
-    it("scope name in scoped package name with non URI safe characters are not supported", () => {
-        assert.deepEqual(validatePackageName("@  scope  /bar"), { name: "  scope  ", isScopeName: true, result: NameValidationResult.NameContainsNonURISafeCharacters });
-        assert.deepEqual(validatePackageName("@; say ‘Hello from TypeScript!’ #/bar"), { name: "; say ‘Hello from TypeScript!’ #", isScopeName: true, result: NameValidationResult.NameContainsNonURISafeCharacters });
-        assert.deepEqual(validatePackageName("@  scope  /  bar  "), { name: "  scope  ", isScopeName: true, result: NameValidationResult.NameContainsNonURISafeCharacters });
+    it("scope name in scoped package name with invalid characters are not supported", () => {
+        assert.deepEqual(validatePackageName("@  scope  /bar"), { name: "  scope  ", isScopeName: true, result: NameValidationResult.NameContainsInvalidCharacters });
+        assert.deepEqual(validatePackageName("@; say ‘Hello from TypeScript!’ #/bar"), { name: "; say ‘Hello from TypeScript!’ #", isScopeName: true, result: NameValidationResult.NameContainsInvalidCharacters });
+        assert.deepEqual(validatePackageName("@  scope  /  bar  "), { name: "  scope  ", isScopeName: true, result: NameValidationResult.NameContainsInvalidCharacters });
     });
     it("package name in scoped package name cannot start with dot", () => {
         assert.deepEqual(validatePackageName("@scope/.bar"), { name: ".bar", isScopeName: false, result: NameValidationResult.NameStartsWithDot });
@@ -1551,9 +1552,9 @@ describe("unittests:: tsserver:: typingsInstaller:: Validate package name:", ()
     it("package name in scoped package name cannot start with underscore", () => {
         assert.deepEqual(validatePackageName("@scope/_bar"), { name: "_bar", isScopeName: false, result: NameValidationResult.NameStartsWithUnderscore });
     });
-    it("package name in scoped package name with non URI safe characters are not supported", () => {
-        assert.deepEqual(validatePackageName("@scope/  bar  "), { name: "  bar  ", isScopeName: false, result: NameValidationResult.NameContainsNonURISafeCharacters });
-        assert.deepEqual(validatePackageName("@scope/; say ‘Hello from TypeScript!’ #"), { name: "; say ‘Hello from TypeScript!’ #", isScopeName: false, result: NameValidationResult.NameContainsNonURISafeCharacters });
+    it("package name in scoped package name with invalid characters are not supported", () => {
+        assert.deepEqual(validatePackageName("@scope/  bar  "), { name: "  bar  ", isScopeName: false, result: NameValidationResult.NameContainsInvalidCharacters });
+        assert.deepEqual(validatePackageName("@scope/; say ‘Hello from TypeScript!’ #"), { name: "; say ‘Hello from TypeScript!’ #", isScopeName: false, result: NameValidationResult.NameContainsInvalidCharacters });
     });
 });
 
diff --git a/tests/baselines/reference/tsserver/typingsInstaller/malformed-packagejson.js b/tests/baselines/reference/tsserver/typingsInstaller/malformed-packagejson.js
index b32a3c36b7636..27c9be5bd0cc8 100644
--- a/tests/baselines/reference/tsserver/typingsInstaller/malformed-packagejson.js
+++ b/tests/baselines/reference/tsserver/typingsInstaller/malformed-packagejson.js
@@ -200,7 +200,7 @@ Info seq  [hh:mm:ss:mss] FileWatcher:: Added:: WatchInfo: /home/src/projects/pro
 Info seq  [hh:mm:ss:mss] DirectoryWatcher:: Added:: WatchInfo: /home/src/projects/project/node_modules 1 undefined Project: /dev/null/inferredProject1* WatchType: Directory location for typing installer
 Info seq  [hh:mm:ss:mss] Elapsed:: *ms DirectoryWatcher:: Added:: WatchInfo: /home/src/projects/project/node_modules 1 undefined Project: /dev/null/inferredProject1* WatchType: Directory location for typing installer
 TI:: [hh:mm:ss:mss] Installing typings ["co } }"]
-TI:: [hh:mm:ss:mss] 'co } }':: Package name 'co } }' contains non URI safe characters
+TI:: [hh:mm:ss:mss] 'co } }':: Package name 'co } }' contains invalid characters
 TI:: [hh:mm:ss:mss] All typings are known to be missing or invalid - no need to install more typings
 TI:: [hh:mm:ss:mss] Sending response:
     {
diff --git a/tests/baselines/reference/tsserver/typingsInstaller/should-handle-node-core-modules.js b/tests/baselines/reference/tsserver/typingsInstaller/should-handle-node-core-modules.js
index 3bc84f2df7cd2..29afbcf692263 100644
--- a/tests/baselines/reference/tsserver/typingsInstaller/should-handle-node-core-modules.js
+++ b/tests/baselines/reference/tsserver/typingsInstaller/should-handle-node-core-modules.js
@@ -654,7 +654,7 @@ TI:: [hh:mm:ss:mss] Sending response:
       "projectName": "/dev/null/inferredProject1*"
     }
 TI:: [hh:mm:ss:mss] Installing typings ["s tream"]
-TI:: [hh:mm:ss:mss] 's tream':: Package name 's tream' contains non URI safe characters
+TI:: [hh:mm:ss:mss] 's tream':: Package name 's tream' contains invalid characters
 TI:: [hh:mm:ss:mss] All typings are known to be missing or invalid - no need to install more typings
 TI:: [hh:mm:ss:mss] Sending response:
     {
diff --git a/tests/baselines/reference/tsserver/typingsInstaller/should-not-initialize-invaalid-package-names.js b/tests/baselines/reference/tsserver/typingsInstaller/should-not-initialize-invaalid-package-names.js
index 499d7ad5544a9..d29fb6696c67f 100644
--- a/tests/baselines/reference/tsserver/typingsInstaller/should-not-initialize-invaalid-package-names.js
+++ b/tests/baselines/reference/tsserver/typingsInstaller/should-not-initialize-invaalid-package-names.js
@@ -160,7 +160,7 @@ Info seq  [hh:mm:ss:mss] FileWatcher:: Added:: WatchInfo: /home/src/projects/pro
 Info seq  [hh:mm:ss:mss] DirectoryWatcher:: Added:: WatchInfo: /home/src/projects/project/node_modules 1 undefined Project: /dev/null/inferredProject1* WatchType: Directory location for typing installer
 Info seq  [hh:mm:ss:mss] Elapsed:: *ms DirectoryWatcher:: Added:: WatchInfo: /home/src/projects/project/node_modules 1 undefined Project: /dev/null/inferredProject1* WatchType: Directory location for typing installer
 TI:: [hh:mm:ss:mss] Installing typings ["; say ‘Hello from TypeScript!’ #"]
-TI:: [hh:mm:ss:mss] '; say ‘Hello from TypeScript!’ #':: Package name '; say ‘Hello from TypeScript!’ #' contains non URI safe characters
+TI:: [hh:mm:ss:mss] '; say ‘Hello from TypeScript!’ #':: Package name '; say ‘Hello from TypeScript!’ #' contains invalid characters
 TI:: [hh:mm:ss:mss] All typings are known to be missing or invalid - no need to install more typings
 TI:: [hh:mm:ss:mss] Sending response:
     {