Error when verifying QSPI Flash

[Altera_Forum]

Hello - I am getting the message below intermittently during the verify of an FPGA (and spl at times) image. 

The FPGA does not load so there may be another problem too but I was wondering if anyone has seen this and if so, resolved it?  Current hardware is: USB-Blaster [USB-1] Found HPS at device 1  Double check JTAG chain HPS Device IDCODE: 0x4BA00477 AHB Port is located at port 0 APB Port is located at port 1  Double check device identification ... Boot Info: 3.0V QSPI Flash Clock Select: 0 Start HPS Quad SPI flash programming ... Initialize QSPI peripheral and flash controller ...  Assuming QSPI controller system clock is 50Mhz  QSPI controller baudrate setting: 32 (15) Read Silicon ID of Quad SPI flash ...  Quad SPI Flash silicon ID is 0x1020BA20  Flash device matched  Manufacturer: MICRON  Device: QSPI_512  Assuming QSPI controller system clock is 50Mhz  QSPI controller baudrate setting: 2 (0) Enable Four Byte Addressing ... Verify Quad SPI flash ...  Progress [****????????????????] 22% Error: Encounter invalid ACK status while accessing HPS Error: Bulk read failure: Failed to read data in bulk Error: Quartus Prime Programmer was unsuccessful. 0 errors, 0 warnings  Error: Peak virtual memory: 138 megabytes  Error: Processing ended: Thu Nov 17 20:27:36 2016  Error: Elapsed time: 00:26:49  Error: Total CPU time (on all processors): 00:01:09  Thanks Kevin.