diff --git a/src/libCom/osi/os/WIN32/osdEvent.c b/src/libCom/osi/os/WIN32/osdEvent.c
index c25ee5f65..9d300e71c 100644
--- a/src/libCom/osi/os/WIN32/osdEvent.c
+++ b/src/libCom/osi/os/WIN32/osdEvent.c
@@ -84,7 +84,7 @@ epicsShareFunc epicsEventStatus epicsEventWait ( epicsEventId pSem )
     }
 }
 
-extern HANDLE osdThreadGetTimer();
+extern HANDLE osdThreadGetTimer(void); /* from osdThread.c */
 
 /*
  * epicsEventWaitWithTimeout ()
@@ -92,7 +92,7 @@ extern HANDLE osdThreadGetTimer();
 epicsShareFunc epicsEventStatus epicsEventWaitWithTimeout (
     epicsEventId pSem, double timeOut )
 { 
-    static const unsigned nSec100PerSec = 10000000;
+    static const unsigned nSec100PerSec = 10000000u;
     HANDLE handles[2];
     DWORD status;
     LARGE_INTEGER tmo;
@@ -102,14 +102,12 @@ epicsShareFunc epicsEventStatus epicsEventWaitWithTimeout (
         tmo.QuadPart = 0u;
     }
     else {
-        tmo.QuadPart = -((LONGLONG)(timeOut * nSec100PerSec + 0.5));  // +0.99999999 ?
+        tmo.QuadPart = -((LONGLONG)(timeOut * nSec100PerSec + 0.5));
     }
 
     if (tmo.QuadPart < 0) {
         timer = osdThreadGetTimer();
-        if (!SetWaitableTimer(timer, &tmo, 0, NULL, NULL, 0))
-        {
-            printf("event error %d\n", GetLastError());
+        if (!SetWaitableTimer(timer, &tmo, 0, NULL, NULL, 0)) {
             return epicsEventError;
         }
         handles[0] = pSem->handle;
@@ -123,10 +121,11 @@ epicsShareFunc epicsEventStatus epicsEventWaitWithTimeout (
         return epicsEventOK;
     }
     else if ( status == WAIT_OBJECT_0 + 1 || status == WAIT_TIMEOUT ) {
+        /* WaitForMultipleObjects will trigger WAIT_OBJECT_0 + 1,
+           WaitForSingleObject will trigger WAIT_TIMEOUT */
         return epicsEventWaitTimeout;
     }
     else {
-        printf("event error %d\n", GetLastError());
         return epicsEventError;
     }
 }
diff --git a/src/libCom/osi/os/WIN32/osdThread.c b/src/libCom/osi/os/WIN32/osdThread.c
index a5c455dac..1b590de27 100644
--- a/src/libCom/osi/os/WIN32/osdThread.c
+++ b/src/libCom/osi/os/WIN32/osdThread.c
@@ -528,6 +528,9 @@ static win32ThreadParam * epicsThreadParmCreate ( const char *pName )
         pParmWIN32->isSuspended = 0;
 #ifdef CREATE_WAITABLE_TIMER_HIGH_RESOLUTION
         pParmWIN32->timer = CreateWaitableTimerEx(NULL, NULL, CREATE_WAITABLE_TIMER_HIGH_RESOLUTION, TIMER_ALL_ACCESS);
+        if (pParmWIN32->timer == NULL) {
+            pParmWIN32->timer = CreateWaitableTimer(NULL, 0, NULL);
+        }
 #else
         pParmWIN32->timer = CreateWaitableTimer(NULL, 0, NULL);
 #endif
@@ -769,6 +772,10 @@ epicsShareFunc int epicsShareAPI epicsThreadIsSuspended ( epicsThreadId id )
     }
 }
 
+/**
+ * osdThreadGetTimer ()
+ * return stored waitable timer object for thread
+ */
 HANDLE osdThreadGetTimer()
 {
     win32ThreadGlobal * pGbl = fetchWin32ThreadGlobal ();
@@ -787,7 +794,7 @@ HANDLE osdThreadGetTimer()
  */
 epicsShareFunc void epicsShareAPI epicsThreadSleep ( double seconds )
 {
-    static const unsigned nSec100PerSec = 10000000;
+    static const unsigned nSec100PerSec = 10000000u;
     LARGE_INTEGER tmo;
     HANDLE timer;
 
@@ -795,7 +802,7 @@ epicsShareFunc void epicsShareAPI epicsThreadSleep ( double seconds )
         tmo.QuadPart = 0u;
     }
     else {
-        tmo.QuadPart = -((LONGLONG)(seconds * nSec100PerSec + 0.5)); // +0.99999999 ?
+        tmo.QuadPart = -((LONGLONG)(seconds * nSec100PerSec + 0.5));
     }
 
     if (tmo.QuadPart == 0) {
@@ -803,14 +810,12 @@ epicsShareFunc void epicsShareAPI epicsThreadSleep ( double seconds )
     }
     else {
         timer = osdThreadGetTimer();
-        if (!SetWaitableTimer(timer, &tmo, 0, NULL, NULL, 0))
-        {
-            printf("timer error %d\n", GetLastError());
+        if (!SetWaitableTimer(timer, &tmo, 0, NULL, NULL, 0)) {
+            fprintf ( stderr, "epicsThreadSleep: SetWaitableTimer failed %lu\n", GetLastError() );
             return;
         }
-        if (WaitForSingleObject(timer, INFINITE) != WAIT_OBJECT_0)
-        {
-            printf("timer error %d\n", GetLastError());
+        if (WaitForSingleObject(timer, INFINITE) != WAIT_OBJECT_0) {
+            fprintf ( stderr, "epicsThreadSleep: WaitForSingleObject failed %lu\n", GetLastError() );
         }
     }
 }