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.


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.

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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! :)


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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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