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Cannot open MDF files

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Any help would be appreciated.  I'm trying to open *.mdf files.  They load, but show no data.  Checking custom properties it shows that they were generated by "MDF4Lib" with Version MDF 4.1.  I don't know but this could mean that they are MDF 4 files, but they don't have the *.mf4 extension.


I installed the MDF4 Data Plugin, but this doesn't seem to solve the problem.  When I try to load files, I can choose MDF3 (as *.mdf) or mdf4_ugn (as *.mf4).  I cannot choose MDF4 as a *.mdf file.


I'm running Diadem 2019 Advanced edition.  


Any suggestions?

Thanks all!



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First, verify the MDF file format is valid by using Vector's MDF file validator (free download).   This may help you identify if it is a MDF3 or MDF4 file format.  


I found that the MDF3 file formats varied considerably by each vendor's implementation.  


Please identify for  NI the version of the DataPlugin you are using to try to load the MDF file.  


I found some sample MDF files online here:  https://canlogger.csselectronics.com/canedge-getting-started/log-file-tools/.  However, when I attempted to read the J1939-DBC-MDF4 file named "7F34B296_00000009_00000008.mf4" with DIAdem 2019 and the MDF4 DataPlugin version, I received no error, but no channel groups or channels.  I was able to read the file "7F34B296_00000009_00000008-scaled.mf4" without issue.  I experienced the same situation for the pair of files under "OBD2-DBC-MDF4".  I know that MDF4 files can have different formats, so I suspect only one file from each is of the format that DIAdem can read.  





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Hi All:


Problem solved thanks to Cici at NI Support.  The problem was the *.uri file that contains the Data Plugin wasn't being copied into the right folder location during the setup process.  As a result, Diadem wasn't getting the right plugin.


Rather than locating the file here:

C:\Program Files\National Instruments\Shared\USI\DataPlugins\MDF4


it was being rather located here:

C:\Program Files (x86)\National Instruments\Shared\USI\DataPlugins\MDF4


It seems my "bitness" was the problem.  I'm running the 64-bit application.


Once I moved the MDF4.uri to the right location, I was able to add it through the Diadem settings.


Thanks to markwkiehl for your assistance, and NI Support!

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