diff --git a/site_ansto/anstohttp.c b/site_ansto/anstohttp.c
index 85f74272..82becf5e 100644
--- a/site_ansto/anstohttp.c
+++ b/site_ansto/anstohttp.c
@@ -671,7 +671,7 @@ static int AnstoHttpGetHistogram(pHistDriver self, SConnection *pCon,
 // Note, actual transfer of such large data sizes in one hit may fail, not recommended.
 //#define MAX_HTTP_REQUEST_BYTES 131072
 //#define MAX_HTTP_REQUEST_BYTES 1048576
-#define MAX_HTTP_REQUEST_BYTES (4096*1048576) // max transfer size 4GB (but your mileage may vary)
+#define MAX_HTTP_REQUEST_BYTES (((long long)4096)*1048576) // max transfer size 4GB (but your mileage may vary)
 // Do the HTTP data transfer in bite sized pieces
 	while(end>start)
 	{
@@ -680,7 +680,7 @@ static int AnstoHttpGetHistogram(pHistDriver self, SConnection *pCon,
 		
 	    snprintf(command,255,"%s?bank=%d&start=%d&end=%d",gethm,bank,
 	        start,start+size);
-	
+		
 	    status = anstoHttpGet(pPriv,command);
 	    if(status != 1){
 	        return HWFault;