Had physical film converted to mp4. In Movie Maker 12 loaded mp4 ok, can view complete film, but all thumbnails show only the first frame. Screen shot available.

DxDiag shows:Operating System: Windows 8.1 64-bit (6.3, Build 9600) (9600.winblue_gdr.140330-1035)
           Language: English (Regional Setting: English)
System Manufacturer: Hewlett-Packard
       System Model: HP Pavilion 15 Notebook PC
               BIOS: F.33
          Processor: AMD A6-5350M APU with Radeon(tm) HD Graphics    (2 CPUs), ~2.9GHz
             Memory: 4096MB RAM
Available OS Memory: 3270MB RAM
          Page File: 2351MB used, 2134MB available
        Windows Dir: C:WINDOWS
    DirectX Version: DirectX 11
DX Setup Parameters: Not found
   User DPI Setting: Using System DPI
 System DPI Setting: 96 DPI (100 percent)
    DWM DPI Scaling: Disabled
     DxDiag Version: 6.03.9600.16384 64bit Unicode

------------
DxDiag Notes
------------
      Display Tab 1: No problems found.
        Sound Tab 1: No problems found.
          Input Tab: No problems found.

MediaInfo shows:

Format                                   : MPEG-4
Format profile                           : Base Media / Version 2
Codec ID                                 : mp42
File size                                : 458 MiB
Duration                                 : 16mn 16s
Overall bit rate mode                    : Variable
Overall bit rate                         : 3 934 Kbps
Encoded date                             : UTC 2014-08-26 21:09:46
Tagged date                              : UTC 2014-08-26 21:09:46

Video
ID                                       : 1
Format                                   : MPEG-4 Visual
Format profile                           : Simple@L3
Format settings, BVOP                    : No
Format settings, QPel                    : No
Format settings, GMC                     : No warppoints
Format settings, Matrix                  : Default (H.263)
Codec ID                                 : 20
Duration                                 : 16mn 16s
Bit rate mode                            : Variable
Bit rate                                 : 3 800 Kbps
Maximum bit rate                         : 4 791 Kbps
Width                                    : 640 pixels
Height                                   : 480 pixels
Display aspect ratio                     : 4:3
Frame rate mode                          : Variable
Frame rate                               : 29.970 fps
Minimum frame rate                       : 29.940 fps
Maximum frame rate                       : 29.970 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Compression mode                         : Lossy
Bits/(Pixel*Frame)                       : 0.413
Stream size                              : 442 MiB (97%)
Language                                 : English
Encoded date                             : UTC 2014-08-26 21:09:46
Tagged date                              : UTC 2014-08-26 21:09:46