diff --git a/.appveyor.yml b/.appveyor.yml
index 4ec05f8c7d5..2a67567e476 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -14,34 +14,36 @@ environment:
 
 cache:
   - 'C:\Users\appveyor\.cargo'
+  - target
 
 install:
-  - appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
-  - rustup-init.exe -yv --default-host %target%
+  # uncomment these lines if the cache is cleared, or if we must re-install rust for some reason
+  # - appveyor DownloadFile https://win.rustup.rs/ -FileName rustup-init.exe
+  # - rustup-init.exe -yv --default-host %target%
   - set PATH=%PATH%;%USERPROFILE%\.cargo\bin
+  - rustup default stable-%target%
+  - rustup update
   - rustc -vV
   - cargo -vV
   # Install InnoSetup
   - appveyor-retry appveyor DownloadFile https://s3-us-west-1.amazonaws.com/rust-lang-ci2/rust-ci-mirror/2017-08-22-is.exe
   - 2017-08-22-is.exe /VERYSILENT /SUPPRESSMSGBOXES /NORESTART /SP-
   - set PATH="C:\Program Files (x86)\Inno Setup 5";%PATH%
+# uncomment to RDP to appveyor
+#  - ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))
 
 build_script:
-  - cargo build --verbose
+   - cargo build --release --verbose
 
 test_script:
-  - set RUST_BACKTRACE=1
-  - cd ./lib/spectests && cargo test -- --test-threads 1 && cd ../..
+  - cargo test --package wasmer-spectests
 
-before_deploy:
+after_build:
   - cd ./src/installer
   - iscc wasmer.iss
   - copy /y .\WasmerInstaller.exe ..\..\WasmerInstaller-%APPVEYOR_REPO_TAG_NAME%.exe
-  - appveyor PushArtifact WasmerInstaller-%APPVEYOR_REPO_TAG_NAME%.exe
-
-artifacts:
-  - path: WasmerInstaller-%APPVEYOR_REPO_TAG_NAME%.exe
-    name: WasmerInstaller.exe
+  - appveyor PushArtifact ..\..\WasmerInstaller-%APPVEYOR_REPO_TAG_NAME%.exe
+  - cd ..\..\
 
 deploy:
   description: 'WasmerInstaller'
diff --git a/lib/runtime-core/src/sys/windows/memory.rs b/lib/runtime-core/src/sys/windows/memory.rs
index 3ca86bec935..d47388170d2 100644
--- a/lib/runtime-core/src/sys/windows/memory.rs
+++ b/lib/runtime-core/src/sys/windows/memory.rs
@@ -33,7 +33,7 @@ impl Memory {
 
         let protect = protection.to_protect_const();
 
-        let ptr = unsafe { VirtualAlloc(ptr::null_mut(), size, MEM_RESERVE | MEM_COMMIT, protect) };
+        let ptr = unsafe { VirtualAlloc(ptr::null_mut(), size, MEM_RESERVE, protect) };
 
         if ptr.is_null() {
             Err("unable to allocate memory".to_string())
@@ -57,14 +57,7 @@ impl Memory {
 
         let size = round_up_to_page_size(size, page_size::get());
 
-        let ptr = unsafe {
-            VirtualAlloc(
-                ptr::null_mut(),
-                size,
-                MEM_RESERVE | MEM_COMMIT,
-                PAGE_NOACCESS,
-            )
-        };
+        let ptr = unsafe { VirtualAlloc(ptr::null_mut(), size, MEM_RESERVE, PAGE_NOACCESS) };
 
         if ptr.is_null() {
             Err(MemoryCreationError::VirtualMemoryAllocationFailed(
diff --git a/lib/win-exception-handler/exception_handling/exception_handling.c b/lib/win-exception-handler/exception_handling/exception_handling.c
index 3284034cc23..eb45b204de0 100644
--- a/lib/win-exception-handler/exception_handling/exception_handling.c
+++ b/lib/win-exception-handler/exception_handling/exception_handling.c
@@ -10,6 +10,7 @@ __declspec(thread) DWORD64 caughtInstructionPointer;
 __declspec(thread) PVOID savedStackPointer;
 __declspec(thread) BOOL exceptionHandlerInstalled = FALSE;
 __declspec(thread) BOOL alreadyHandlingException = FALSE;
+__declspec(thread) PVOID handle;
 
 void longjmpOutOfHere() {
     longjmp(jmpBuf, 1);
@@ -38,6 +39,14 @@ exceptionHandler(struct _EXCEPTION_POINTERS *ExceptionInfo) {
     return EXCEPTION_CONTINUE_EXECUTION;
 }
 
+static void removeExceptionHandler() {
+    if (exceptionHandlerInstalled == FALSE) {
+        return;
+    }
+    RemoveVectoredExceptionHandler(handle);
+    exceptionHandlerInstalled = FALSE;
+}
+
 uint8_t callProtected(trampoline_t trampoline,
         const struct wasmer_instance_context_t* ctx,
         const struct func_t* func,
@@ -48,7 +57,7 @@ uint8_t callProtected(trampoline_t trampoline,
     // install exception handler
     if (exceptionHandlerInstalled == FALSE) {
         exceptionHandlerInstalled = TRUE;
-        AddVectoredExceptionHandler(CALL_FIRST, exceptionHandler);
+        handle = AddVectoredExceptionHandler(CALL_FIRST, exceptionHandler);
     }
 
     // jmp jmp jmp!
@@ -60,6 +69,8 @@ uint8_t callProtected(trampoline_t trampoline,
         out_result->code = 0;
         out_result->exceptionAddress = 0;
         out_result->instructionPointer = 0;
+
+        removeExceptionHandler();
         return TRUE;
     }
 
@@ -70,5 +81,6 @@ uint8_t callProtected(trampoline_t trampoline,
     caughtExceptionAddress = 0;
     caughtInstructionPointer = 0;
 
+    removeExceptionHandler();
     return FALSE;
 }