MATLAB Answers


mclmcrrt77.dll missing after installing Windows 7?

Asked by Cathy
on 9 Jun 2011
Latest activity Answered by hervineau sebastien on 19 Sep 2016

After OS upgrade to Windows 7 from XP, my .exe stopped working. The error message says: "The program can't start because mclmcrrt77.dll is missing from your computer. Try reinstalling the program to fix this progblem."

I tried to rerun MCRInstall.exe but it didn't help. (MCR v7.7)

Please help~



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3 Answers

Answer by Walter Roberson
on 9 Jun 2011

Possibly a PATH problem. See this solution

Question: did you go from 32 bit to 64 bit? If so then you will need a different MCR, I believe.


on 9 Jun 2011

I think this might be the exact problem! I found I am upgraded to 64 bit. Do you know where to download the 64-bit MCR? thanks a lot!!

You will need to have the person who compiled the application to provide you with the 64-bit version of the MCR (it is included with a 64-bit installation of MATLAB Compiler). The MCR cannot be placed for public download for licensing reasons.

However, note that users have been able to have 32-bit MCR running on 64-bit Windows in the past - see

I think the real reason in your case is that $mcr_root\ver\runtime\win32 has not been added to your system path. I find that on Windows 7, if you don't run installers as Administrator, it doesn't not give them privileges to perform operations like modifying the system path.

Answer by Cathy
on 15 Jun 2011

Yes the 32-bit MCR works on 64-bit Windows. The trick is just to restart the computer after the installation. Thanks to all! :)


Answer by hervineau sebastien on 19 Sep 2016

Try this research mclmcrrt77.dll on your computer and delete all the founds

or go to C:\Windows\System32 and delete the file mclmcrrt77.dll if you have and go to C:\Windows\SysWOW64 to delete again ,

And try to ré-install MCRInstaller.exe ( install on c: ) the typical install ....


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