diff --git a/src/client/common/process/proc.ts b/src/client/common/process/proc.ts
index 959d9b615f39..059302c9d349 100644
--- a/src/client/common/process/proc.ts
+++ b/src/client/common/process/proc.ts
@@ -15,9 +15,10 @@ export class ProcessService implements IProcessService {
     constructor( @inject(IBufferDecoder) private decoder: IBufferDecoder) { }
     public execObservable(file: string, args: string[], options: SpawnOptions = {}): ObservableExecutionResult<string> {
         const encoding = options.encoding = typeof options.encoding === 'string' && options.encoding.length > 0 ? options.encoding : DEFAULT_ENCODING;
+        delete options.encoding;
         const spawnOptions = { ...options };
         if (!spawnOptions.env || Object.keys(spawnOptions).length === 0) {
-            spawnOptions.env = process.env;
+            spawnOptions.env = { ...process.env };
         }
 
         // Always ensure we have unbuffered output.
@@ -74,9 +75,10 @@ export class ProcessService implements IProcessService {
     }
     public async exec(file: string, args: string[], options: SpawnOptions = {}): Promise<ExecutionResult<string>> {
         const encoding = options.encoding = typeof options.encoding === 'string' && options.encoding.length > 0 ? options.encoding : DEFAULT_ENCODING;
+        delete options.encoding;
         const spawnOptions = { ...options };
         if (!spawnOptions.env || Object.keys(spawnOptions).length === 0) {
-            spawnOptions.env = process.env;
+            spawnOptions.env = { ...process.env };
         }
 
         // Always ensure we have unbuffered output.
diff --git a/src/test/common/process/proc.exec.test.ts b/src/test/common/process/proc.exec.test.ts
index 8ab71804d3d2..f04e77e1b9f4 100644
--- a/src/test/common/process/proc.exec.test.ts
+++ b/src/test/common/process/proc.exec.test.ts
@@ -35,7 +35,7 @@ suite('ProcessService', () => {
     test('exec should output print unicode characters', async () => {
         const procService = new ProcessService(new BufferDecoder());
         const printOutput = 'öä';
-        const result = await procService.exec(pythonPath, ['-c', `print(u"${printOutput}")`]);
+        const result = await procService.exec(pythonPath, ['-c', `print("${printOutput}")`]);
 
         expect(result).not.to.be.an('undefined', 'result is undefined');
         expect(result.stdout.trim()).to.be.equal(printOutput, 'Invalid output');