diff --git a/src/windows/wdfserial/QCPNP.c b/src/windows/wdfserial/QCPNP.c
index c8ed894..99fa4a4 100644
--- a/src/windows/wdfserial/QCPNP.c
+++ b/src/windows/wdfserial/QCPNP.c
@@ -3112,6 +3112,18 @@ NTSTATUS QCPNP_ResetUsbPipe
 )
 {
     NTSTATUS status = STATUS_SUCCESS;
+
+    if (usbPipe == NULL)
+    {
+        QCSER_DbgPrint
+        (
+            QCSER_DBG_MASK_CIRP,
+            QCSER_DBG_LEVEL_ERROR,
+            ("<%ws> QCPNP_ResetUsbPipe called with NULL pipe, skipping\n", pDevContext->PortName)
+        );
+        return STATUS_SUCCESS;
+    }
+
     WDFIOTARGET ioTarget = WdfUsbTargetPipeGetIoTarget(usbPipe);
     WDF_REQUEST_SEND_OPTIONS syncReqOptions;
     WDF_REQUEST_SEND_OPTIONS_INIT(&syncReqOptions, 0);
diff --git a/src/windows/wdfserial/QCRD.c b/src/windows/wdfserial/QCRD.c
index 6f6699c..979b271 100644
--- a/src/windows/wdfserial/QCRD.c
+++ b/src/windows/wdfserial/QCRD.c
@@ -132,8 +132,8 @@ void QCRD_ReadRequestHandlerThread
     PREQUEST_CONTEXT pReqContext;
     PDEVICE_CONTEXT  pDevContext = pContext;
     ULONG            devErrCnt = 0;
-    WDFIOTARGET      ioTarget = WdfUsbTargetPipeGetIoTarget(pDevContext->BulkIN);
-    PKWAIT_BLOCK     pWaitBlock = ExAllocatePoolUninitialized(NonPagedPoolNx, (READ_THREAD_RESUME_EVENT_COUNT) * sizeof(KWAIT_BLOCK), '3gaT');
+    WDFIOTARGET      ioTarget = NULL;
+    PKWAIT_BLOCK     pWaitBlock = NULL;
     BOOLEAN          bRunning = TRUE;
     BOOLEAN          bDeviceOpened = FALSE;
     BOOLEAN          bDeviceAwaken = FALSE;
@@ -144,6 +144,22 @@ void QCRD_ReadRequestHandlerThread
     WDF_REQUEST_PARAMETERS requestParam;    // for application requests
     PRING_BUFFER rxBuffer = &pDevContext->ReadRingBuffer;
 
+    if (pDevContext->BulkIN == NULL)
+    {
+        QCSER_DbgPrint
+        (
+            QCSER_DBG_MASK_READ,
+            QCSER_DBG_LEVEL_ERROR,
+            ("<%ws> RIRP: QCRD_ReadRequestHandlerThread ERROR no USB pipe for read, exiting\n", pDevContext->PortName)
+        );
+        KeSetEvent(&pDevContext->ReadThreadStartedEvent, IO_NO_INCREMENT, FALSE);
+        PsTerminateSystemThread(STATUS_SUCCESS);
+        return;
+    }
+
+    ioTarget = WdfUsbTargetPipeGetIoTarget(pDevContext->BulkIN);
+    pWaitBlock = ExAllocatePoolUninitialized(NonPagedPoolNx, (READ_THREAD_RESUME_EVENT_COUNT) * sizeof(KWAIT_BLOCK), '3gaT');
+
     if (pWaitBlock == NULL)
     {
         WdfDeviceSetFailed(pDevContext->Device, WdfDeviceFailedNoRestart);
diff --git a/src/windows/wdfserial/QCWT.c b/src/windows/wdfserial/QCWT.c
index c60ee18..0b707d6 100644
--- a/src/windows/wdfserial/QCWT.c
+++ b/src/windows/wdfserial/QCWT.c
@@ -403,7 +403,7 @@ void QCWT_WriteRequestHandlerThread
                         WDF_REQUEST_PARAMETERS_INIT(&writeParam);
                         WdfRequestGetParameters(request, &writeParam);
                         QCWT_EvtIoWrite(pDevContext->WriteQueue, request, writeParam.Parameters.Write.Length);
-                        if (gVendorConfig.EnableZeroLengthPacket && (writeParam.Parameters.Write.Length % pDevContext->wMaxPktSize == 0))
+                        if (gVendorConfig.EnableZeroLengthPacket && (pDevContext->wMaxPktSize != 0) && (writeParam.Parameters.Write.Length % pDevContext->wMaxPktSize == 0))
                         {
 #ifdef QCUSB_MUX_PROTOCOL
                             if (pDevContext->DeviceFunction != QCUSB_DEV_FUNC_LPC)