diff -up hplip-3.9.8/prnt/backend/hp.c.device-reconnected hplip-3.9.8/prnt/backend/hp.c
--- hplip-3.9.8/prnt/backend/hp.c.device-reconnected	2009-09-29 16:02:14.717467334 +0100
+++ hplip-3.9.8/prnt/backend/hp.c	2009-09-29 16:02:20.019342096 +0100
@@ -638,6 +638,7 @@ int main(int argc, char *argv[])
    HPMUD_DEVICE hd=-1;
    HPMUD_CHANNEL cd=-1;
    int n, total=0, retry=0, size, pages;
+   int consecutive_failures=0;
    enum HPMUD_RESULT stat;
    char *printer = getenv("PRINTER"); 
    
@@ -789,10 +790,23 @@ int main(int argc, char *argv[])
                /* IO error, get printer status. */
                if (loop_test(hd, cd, &pa, argv[0], printer, argv[2], argv[1], argv[3]))
                   goto bugout;
+
+               if (++consecutive_failures == 5)
+               {
+                  /* hpmud_write_channel has failed several times in
+                   * succession but the Device ID-based status says
+                   * the printer is happy.  Time to face the fact that
+                   * the device has probably reconnected, and our USB
+                   * channel is invalidated. */
+
+                  BUG("ERROR: device reconnected?");
+                  goto bugout;
+               }
             }
             else
             {
                /* Data was sent to device successfully. */ 
+               consecutive_failures = 0;
                if (pa.pjl_device)
                {
                   /* Laserjets have a large data buffer, so manually check for operator intervention condition. */