Unable to record or export mp4

Problem: “Error: Could not open video encoder” when trying to screen capture using “H264/MPEG-4 AVC” and when trying to export to MP4. I had no problem with version 6.x, now that I am using version 7, I am seeing this error. I am able to record using defaults settings and export to other formats, but I need to export to MP4 for compatibility.

ActivePresenter Version: 7.2.3

OS: Windows 7 Enterprise

From log file:
2018-05-15 13:03:29: Start capturing. Mode: Full motion. Method: 0. Capture Size: (1920, 1200)
2018-05-15 13:03:29: Video Codec: h264_mf. Expecting FPS: 30.00
2018-05-15 13:03:29: Video will be recorded to: C:\Users\steven.hetfield\Documents\ActivePresenter.ActivePresenterCachedProjects\Untitled_tempdir\video_20180515_13-03-29.mkv
2018-05-15 13:03:29: bgr24 pixel format is not supported, nv12 will be used
2018-05-15 13:03:29: RLMedia: MFT name: ‘H264 Encoder MFT’
2018-05-15 13:03:29: RLMedia: MF Setting Framerate: 30 / 1
2018-05-15 13:03:29: RLMedia: MF Setting Quality: 90
2018-05-15 13:03:29: RLMedia: MF Setting GOPSize: 30
2018-05-15 13:03:29: RLMedia: MF Enabling CABAC FAILED: 0x80004001
2018-05-15 13:03:29: RLMedia: could not set output type (80004005)
2018-05-15 13:03:29: VideoRecorder: Could not open output file with specified format.
2018-05-15 13:03:29: Error: Could not open video encoder


It looks like CABAC coding is not available on Windows 7 Enterprise. That causes the encoding to MP4 H264 failed.
Can you please confirm if you have installed all the updates?


I’m using
ActivePresenter Version: 7.2.3
OS: Windows 7 Pro (64 bit)

I cannot export in MP4 because it says there is an error with the video codex


ActivePresenter Updates? I have 7.2.3 as stated.
OS updates: Windows 7 Enterprise Service Pack 1.

I can, however, export with resolution lower than 1920 X 1200. (e.g. 1440 x 1080 exports successfully)

It depends on OS as following:

  • Windows 7: the max resolution is 1920x1080.
  • Windows 10: the max resolution is 4096x2304.


I have the same problem, cannot export as MP4 but other formats work fine! Version 7.5.8. with windows 7 pro. resolution doesnt seem to matter

Hi Alex,

This limitation is only applied for MP4. Other formats should work.