What is in ..\ProgramData\National Instruments\MDF\.

[1984]

Hi,

I'm running low on disk space and noticed that this folder eats 7GB+. Is this something neccessary or could it be deleted? Same with \ProgramData\National Instruments\NI Package Manager\packages\ but I guess the packages can be deleted without an issue.

thx.

[rolfk · Accepted solution]

The MDF folder are the installer packages for the older MSI based NI software installers (pre 2020 or so software applications and drivers). If you delete them you will encounter issues when you try to build installers from LabVIEW Builds and include additional software to add to the installer. The Installer Builder will try to use the packages in this folder to built the installer and if it can't find it it will prompt you for the installer images and that can be a tricky thing to tackle. It's not just like you could point it at any installer image for that component but it needs to be EXACTLY the image that was used to install the software on your machine. And yes that means that if you downloaded the software it wants that installer image, and not some other installer image from an USB stick even if the version actually seems the same. And if it was a downloaded installer it is likely that the currently downloadable installer isn't exactly the same as NI regularly releases bug fixes and updates the download site to serve the latest bug fix release, without providing alternate links for older bug fix releases.

The ni packages are similar but for newer software versions. The exact details are somewhat different but generally NI Package Manager is rather picky about things and the according NI Package Builder isn't better.

[Hooovahh]

Here is an article on the folder you are asking about.  Large amounts of my development are in a single version of LabVIEW.  Then a new version will come out and programs will be migrated to a new version.  As a result my MDF folder will balloon with files from versions I no longer use.  So once a year or so I will delete my MDF files.  As Rolf mentioned that will mean the next time you build an installer, LabVIEW will ask for where to find the runtime engines and files needed.  We keep all of our NI installers on the network so finding them is easy enough.  If you archive the installers used, or if you never intend on making an installer using the application builder, you can probably delete these files.

[santo_13]

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@Hooovahh wrote:

Here is an article on the folder you are asking about.  Large amounts of my development are in a single version of LabVIEW.  Then a new version will come out and programs will be migrated to a new version.  As a result my MDF folder will balloon with files from versions I no longer use.  So once a year or so I will delete my MDF files.  As Rolf mentioned that will mean the next time you build an installer, LabVIEW will ask for where to find the runtime engines and files needed.  We keep all of our NI installers on the network so finding them is easy enough.  If you archive the installers used, or if you never intend on making an installer using the application builder, you can probably delete these files.

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Using this article I recovered ~40GB of disk space.