MATLAB (R2014b) keeps crashing when communicating with .dll files.

I am using matlab GUIDE to communicate with some hardware via .dll driver files. I randomly get the following access violation error when communicating with these devices. I cannot pinpoint the exact command which causes the error because it happens randomly each time.

------------------------------------------------------------------------
          Access violation detected at Thu Feb 08 13:14:09 2018
------------------------------------------------------------------------

Configuration:
  Crash Decoding     : Disabled
  Default Encoding   : windows-1252
  Graphics card 1    : NVIDIA ( 0x10de ) NVIDIA GeForce 840M Version 10.18.13.5382
  Graphics card 2    : Intel Corporation ( 0x8086 ) Intel(R) HD Graphics 5500 Version 20.19.15.4531
  MATLAB Architecture: win64
  MATLAB Root        : C:\Program Files\MATLAB\R2014b
  MATLAB Version     : 8.4.0.150421 (R2014b)
  Operating System   : Microsoft Windows 7 Professional 
  Processor ID       : x86 Family 6 Model 61 Stepping 4, GenuineIntel
  Software OpenGL    : 1
  Virtual Machine    : Java 1.7.0_11-b21 with Oracle Corporation Java HotSpot(TM) 64-Bit Server VM mixed mode
  Window System      : Version 6.1 (Build 7601: Service Pack 1)

Fault Count: 1

Abnormal termination:
Access violation

Register State (from fault):
  RAX = 000000002e26fc40  RBX = 00000000ff988fc0
  RCX = 00000000ff988fc0  RDX = 0000ff9803408800
  RSP = 000000002e26fb88  RBP = 000000000022016c
  RSI = 000000002e26fca8  RDI = 0000000000000004

     R8 = 000000002e26fca8   R9 = 0000000000000004
    R10 = 0000000000000000  R11 = 0000000000000246
    R12 = 0000000000001388  R13 = 0000000000000000
    R14 = 0000000000000000  R15 = 0000000000000000

    RIP = 000000000e8b3065  EFL = 00010202

     CS = 0033   FS = 0053   GS = 002b

Stack Trace (from fault):
[  0] 0x000000000e8b3065                     C:\Windows\system32\FTD2XX.dll+00012389
[  1] 0x000000000e8b5ea4                     C:\Windows\system32\FTD2XX.dll+00024228 FT_IoCtl+00000036
[  2] 0x000000000e8b5d87                     C:\Windows\system32\FTD2XX.dll+00023943 FT_GetQueueStatus+00000055
[  3] 0x000007fef670b98c C:\Users\Justin\Desktop\Code\GlazLabView_6_1_x64_correct\GlazLabView64\GlazCam\GlazLib.dll+00244108 writeAllScansToFile+00210796
[  4] 0x000007fef6708cd5 C:\Users\Justin\Desktop\Code\GlazLabView_6_1_x64_correct\GlazLabView64\GlazCam\GlazLib.dll+00232661 writeAllScansToFile+00199349
[  5] 0x000007fef6709cc0 C:\Users\Justin\Desktop\Code\GlazLabView_6_1_x64_correct\GlazLabView64\GlazCam\GlazLib.dll+00236736 writeAllScansToFile+00203424
[  6] 0x00000000ec02373c C:\Users\Justin\Desktop\Code\GlazLabView_6_1_x64_correct\GlazLabView64\GlazCam\Qt5Core.dll+00145212 QThread::start+00000748
[  7] 0x000007feecd43fef C:\Program Files\MATLAB\R2014b\bin\win64\MSVCR110.dll+00147439 beginthreadex+00000263
[  8] 0x000007feecd44196 C:\Program Files\MATLAB\R2014b\bin\win64\MSVCR110.dll+00147862 endthreadex+00000402
[  9] 0x00000000779559cd                   C:\Windows\system32\kernel32.dll+00088525 BaseThreadInitThunk+00000013
[ 10] 0x0000000077b8a561                      C:\Windows\SYSTEM32\ntdll.dll+00173409 RtlUserThreadStart+00000033

If this problem is reproducible, please submit a Service Request via:
    http://www.mathworks.com/support/contact_us/

A technical support engineer might contact you with further information.

Thank you for your help.

[Walter Roberson]

Check to be sure you have the latest D2XX driver, http://www.ftdichip.com/FTDrivers.htm