diff --git a/packages/pyright-scip/src/virtualenv/PythonEnvironment.test.ts b/packages/pyright-scip/src/virtualenv/PythonEnvironment.test.ts
new file mode 100644
index 000000000..40c7db90f
--- /dev/null
+++ b/packages/pyright-scip/src/virtualenv/PythonEnvironment.test.ts
@@ -0,0 +1,10 @@
+import PythonEnvironment from './PythonEnvironment';
+import PythonPackage from './PythonPackage';
+
+test('resolves module paths with Windows and POSIX separators', () => {
+    const packageInfo = new PythonPackage('example', '1.0.0', ['example\\windows.py', 'example/posix.py']);
+    const environment = new PythonEnvironment(new Set(packageInfo.files), '1.0.0', [packageInfo]);
+
+    expect(environment.getPackageForModule('example.windows')).toBe(packageInfo);
+    expect(environment.getPackageForModule('example.posix')).toBe(packageInfo);
+});
diff --git a/packages/pyright-scip/src/virtualenv/PythonEnvironment.ts b/packages/pyright-scip/src/virtualenv/PythonEnvironment.ts
index 0220ea1ed..e32d18b29 100644
--- a/packages/pyright-scip/src/virtualenv/PythonEnvironment.ts
+++ b/packages/pyright-scip/src/virtualenv/PythonEnvironment.ts
@@ -1,7 +1,7 @@
 import * as path from 'path';
 import PythonPackage from './PythonPackage';
 
-const pathSepRegex = new RegExp(path.sep, 'g');
+const pathSepRegex = /[\\/]/g;
 
 export default class PythonEnvironment {
     /// Maps a module name (x.y.z) to an index in this.packages