I'm using R2019b. It is generating the MatlabFileAssocFix.Reg file but unable to run it. Getting the error "Cannot import C:\......: Error accessing the registry.". Any help on this highly appreciated.

Add the following
'mlx' , 'MATLAB Live Script' , '-71' , ...
{'Open', 'uiopen(''%1'',1)'} , {'Run', 'run(''%1'')'} ; ...
to "fileExtCell" will fix the association for "*.mlx". Not sure whether '-71' is correct or not, just simply choose a number that different from others. It works for me with Matlab 2019b. There is no ico file for *.mlx by default, which need to be added to C:\Program Files\Polyspace\R2019b\bin\win64 and named as mlx.ico. I sample copy the one for *.m files. Don't forget to replace the version and the path with the installed one.

Hello Sir,
I am unable to Associate my matlab files with new MATLAB 2020a in MacOS Catalina. Is there any such Fix? or How to do that association? please let me know.
Thank You.

Only a minor foible though, it does not support '.mexa64', or '.mexmaci64' . But it is not important, I think.

Excellent! It works on my MATLAB2020a on Windows 7! Thanks!!!

It's not working for .mlapp extension. Here's the registry Entry:
___________________________________________________
[HKEY_CLASSES_ROOT\.mlapp]
@="MATLAB.mlapp.9.8.0"

[HKEY_CLASSES_ROOT\.mlapp\OpenWithProgids]
"MATLAB.mlapp.9.8.0"=""

[HKEY_CLASSES_ROOT\.mlapp\Versions\MATLAB.mlapp.9.8.0]
"FileVersionMS"=dword:00090008
"FileVersionLS"=dword:00000000

[HKEY_CLASSES_ROOT\MATLAB.mlapp.9.8.0]
@="MATLAB Application"

[HKEY_CLASSES_ROOT\MATLAB.mlapp.9.8.0\DefaultIcon]
@="C:\\Program Files\\Polyspace\\R2020a\\bin\\win64\\mlapp.ico,0"

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.mlapp\OpenWithProgids]
"MATLAB.mlapp.9.8.0"=hex(0):

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.mlapp\OpenWithList]
_______________________________________________________________________________________________

I don't know how to fix this but probably this entry is different than others that are working. The missing entries are:
1. Shell Open
2. Shell Open command
3. Shell Open ddeexec
4. Shell Open ddeexec application
5. Shell Open ddeexec topic
6. Also, in fileExts location, 'Open With List' for .mlapp is missing; and that's why when I double click file, no application list shows. While it pops up for other extensions.

I solved the problem I was facing regarding the registry file. This file also fixed a problem with Write permission in a code that had to write fig to a gif file.
Note: The registry file gets created in the, 'matlab root folder' > 'subfolder that contains matlab.exe'. It is better not to run matlab.exe as an administrator.
Thanks a lot @Patrik Forssén

The registry file is not getting created in the same folder. Does it get created somewhere else or should there be some other reason for which the registry file is not getting created?

hi
I have installed two versions of matlab, i.e. 2013b and 2020a. But I have a problem, it is that the 2020a version manages to launch correctly, on the other hand that of 2020a does not manage to launch.
Please help me.

I don't know why mine is not working, it shows up with the error:

associateFiles
Unrecognized function or variable 'binFolder'.

Error in associateFiles (line 96)
binPath = fullfile(matlabroot, 'bin', binFolder);

Thank you! This worked with Matlab 2020a.

Oh, sorry about that. It's working now. thanks

Thanks very much! That's works in Matlab 2018!

It works! I recommend using the 'deleteadd' option, in case you messed anything up already. Also, don't forget to restart explorer after running the registry, or just reboot your pc.

Thanks so much!!!

Working perfect.
Thank you.

It's working so fine, thanks

purfectt.
1. run .mfile
2. run the created .reg file
3. restart matlab
done

Tried on Windows 10 19041.84 for 2019b. Everything's fixed! Thanks!

I tried it on my MAC for 2016b, but it did not work. Is there a solution for MAC?

Thank you!

Worded on Windows 10 and fixed .m files opening as separate instance. Run as admin and import the registry.

Hi,
can you add the live-script data format?

Great!!! Works perfectly on MATLAB 2019b win10.

Usefull file exchange

Great!!! Works perfect on MATLAB 2019b
Saved me much time, thank you :)

Thanks!
It worked with my MATLAB R2013a on Windows 10 x64.
When you run .m file in Matlab, it will create a registry file in the same folder with .m file.

Works like magic!

Works perfectly on Matlab 2019b on windows7

Thank you!

Great, it solved my problem very well.

This was easy to use and fixed my issue instantly!

Works perfectly on Matlab 2019b on windows10

Worked on Matlab 2019b. Thanks.

Works successfully with R2019b on Windows 10

Works with R2018a on windows 10.

Works with r2019a! Great! Thanks!

Works with r2019b! Great! Thanks!

Perfect!. Thank you so much. r2018a

WOW!! It's like a magic! Thanks!
Work perfectly with matlab 2019a!!

Works perfectly on Matlab R2017a!

This worked!
Just in case this might be useful for someone else: my network blocked the registry file from running on my non-admin account (and right-clicking the .reg file didn't yield a "Run as Admin" option), so I had to open a command prompt as admin and execute "Regedit MatlabFileAssocFix.reg" to update the registry files. That proved successful though.

excelent

Works perfectly with matlab 2018a on windows 10

Many thanks, worked fine on Matlab 2019a on Windows 10.

It worked for me. I was having .m files openedd at Notepad and .mat files oppend at Microsoft Access ! Now both format files are being opened at Matlab, in a single instance. I use Matlab 2018a, Windows 10. Thank you for the developer.

worked perfectly (Win 10, R2019a), many thanks!

Struggled to set new version of Matlab as default program to open Matlab files and then found this thread. Very useful script!

how to associate .mlx (live editor file)?

fixed problem for my win10 2017b

I love you !!!! It fixed all the hassles of opening multiple instances at every double-clicking of .m files!!!!!

fixed my problem with 2018b

it works well for my 2019a.

Fixed my problem with r2019a. Thanks for making that solution so simple!

Works good. Tried on MATLAB 2018a with Windows 10. Solved annoying issue : clicking on .fig or .m or .mat file, a new Matlab instance was opened. After running function, close all Matlab instances, and click on generated Registration entries file, restart Matlab

But it still opens the whole Matlab session, even if I just want to open the Matlab figure file. How to solve that?

It works like a charm!
Finally I can open files from folders without starting a new session of Matlab.

It worked for 2019a.

Worked on Matlab 2016a. Thank you very much!

Thanks a lot for your effort , it worked on 2018b version win 7 64 bit

I uninstalled R2018b after installing 2019a on Windows 10, then it always opens up a new MATLAB instance when double-clicking on .m files.
This file fixed the problem perfectly!
Thank you so much!

Read the instructions and it will work perfectly.

Thank you so much! It helped for Windows 10, MATLAB R2019a

It works, thank you very much!

Thank you so much! (Windows 7 2017b)

thank you, it works perfectly!

thank you very much!! this is very helpful!!

Thank you very much! Great Work!

Worked like a charm!

This code solved the same problem. Thank you for your sharing.

It worked perfect!

Works on R2017b Windows 10
Thank you!

My problem is that m.files, .slx files etc. keep on defaulting to Adobe... so, tiles in this download shows as a PDF and does not work.

Thank you!

Work like magic!

Worked great for me for Matlab 2018b in Windows 10.
Steps:
1) Run the Matlab File to create the registry file
2) Run the created registry file

Simple, fast and perfect (Windows10, 2018b). Thanks!

It didn't work for me

doenst work

nesta3ref bik

Fixed file association problem with windows 10 and R2018b

I was facing with defined problems in above. Simple to use and works perfectly!

perfect....

Worked like a charm. For people having errors showing that "Cannot write registry file". Restart MATLAB and run as administrator. Follow the instructions in the file and done!

Works Fine with R2018 Thanks

perfect with R2018b. Spent hours to figure out how to associate, before finding this

Worked perfectly with R2018b on Windows 10 Pro! Thanks!

Thumbs up! Woks perfectly for 2018a.

Works perfect. Do not forget to run your MATLAB as administrator

can someone give me the steps. i use MATLAB 2018b with windows 10

Worked with Matlab R2017b.

All right! (R2018a)

Maybe you can fix '.mlx' too! :D (file extension of Matlab Live Script)

Worked perfectly with R2018b on Windows 10 Pro!

thanks

worked great windows 10 matlab 2018b

Thank you very much! Works great

Great! (2018a)

Failed to create registry file.

Perfect!!

This worked beautifully for 2018b. Thank you 8D

Worked perfectly for 2018b! Thanks!

Worked for 2017b. Thanks!!!

Worked for 2018a Win10, many thanks!

It worked very well on MATLAB 2018a win10.

I accidentally associated my .m files to Matlab.exe, which then started opening Matlab every time. This file helped fix that problem by updating the registry directly just by simply running the function and running the .reg file that is created. Thank you Patrik for making this!

saved my life.

work for MATLAB R2015a in Windows 10.

Thank you Mr! Hats off to you!

Worked perfectly on MATLAB R2018a

It works for 2018b :) !!

doesn't work on 2018b

One of the best functions that I've used in matlab. Works for 2016a on win10.

Wow. Thank you.
I had updated my Matlab version and the registry would not find 2018a version. This was done on a Windows 7 64bit. As soon as I ran the registryfix file everything worked again.
Again, Thank you

Working on win 64bit Matlab 2017b. Thanks to you!

Works on my win10 64bit + Matlab 2018, many thanks!

work just fine on windows 10 thank you !

Thank you very much! Works like a charm with Matlab 2018a on Windows 7

Thank you very much! It works for Matlab R2017a on Windows 10.

Works for Matlab R2015b on Windows 10

Doesn't work for R2017b for Windows 10.

Works on Windows 10 for MATLAB R2017a

Works for 2018a on windows 7.

Working on 2017b

working on windows 10 MATLAB 2016a

Thanks a lot! it works with MATLAb 2016a/win 10-64.

Perfect! Works for Windows 10, Matlab R2018a. Thank you!

Works! Win 7 Matlab2017b.
Thanks a lot!

Working, Windows 10 R2018a Update 2