Suddenly Matlab does not have permission to do anything!

Hello! I am taking Matlab courses for my Msc, so this is kind of urgent. One day that I wanted to work in Matlab. After I booted it, it gave me a splash screen with java permission access errors and then quit. I ran it as administrator and although it got me into the program, it gave me CD access folder errors. ALL of the files and folders on the left area appeared grey (as in inaccessible), NOT just one or two of them. I re-installed it, and now either it will hang in the splash screen, or if i use the nodesktop command, it will give me this:

"Warning: failed to create preference directory C:\Users\\AppData\Roaming\MathWorks\MATLAB\R2015a.
Check directory permissions.Warning: Userpath must be an absolute path and must exist on disk. "

even though the directory already exists -created by Matlab during the installation.

Th problem can be summed up in this sentence: Suddenly, Matlab has NO access (admin mode or not) in ANY folder or file, even though the previous day everything was smooth.

I am running Windows 8, and the only thing I can think of is that Windows did a silent update, changing some hidden preferences, causing this problem.

[dpb]

Sounds like your supposition may be correct or your machine got infected or the antivirus software has gone amok mayhaps...

Contact TMW at the support link at www.mathworks.com for startup/installation issues.

[Star Strider]

Windows 8 has problems that do not go away even if you update to 8.1.

I always have to warm-reboot at least twice after each update (waiting about 10 minutes between reboots) before it’s finally stable and everything works as it should. I now do this automatically after each update before I launch any applications.

I never had these problems with Windows 7.

Answer 1

[Image Analyst]

Is there a "Nick" between the "\\" in "C:\Users\\AppData\Roaming\MathWorks\MATLAB\R2015a" Actually when I edit the question, I see 7 strange looking symbols as the user name.

&nbsp

Since this is urgent, your fastest solution will be to call the Mathworks on the telephone and talk to a live person. It will be free since this is an installation issue. See the FAQ: http://matlab.wikia.com/wiki/FAQ#After_installation.2C_MATLAB_crashes_or_gives_an_error_message_when_I_try_to_run_MATLAB.

Answer 2

[Nick Agapiou]

Thanks for your help (to all). The only semi-roundabout that i found working is running Matlab through a batch file (create a .bat file in notepad). The code embedded in the file is:

set MATLAB_PREFDIR=C:\MATLABTESTING

   "D:\Program Files\MATLAB\R2015a\bin\matlab.exe"

so that it changes the preferences folder to a folder I created (matlabtesting) and running at the same time the pointed .exe (matlab). For a strange reason it seems to give the permission that way, and only that way (Windows, you never stop to amaze me!). Still, it gives me this error in the command window on matlab startup:

Warning: Userpath must be an absolute path and must exist on disk.
Warning: Userpath must be an absolute path and must exist on disk.

but everything else seems to run smoothly (for the time being it's an -ok- solution, being in a hurry etc)

BTW, warm reboot didn't help, but thanks for pointing it out, might help someone else who stumbles on this thread

[Image Analyst]

What did tech support tell you? You DID call them for free telephone support didn't you?

[Nick Agapiou]

Yes, I called mentorhellas which is the representative / distributor of Matlab in Greece. More or less they told me whatever is already being discussed already in this thread

[Image Analyst]

Call them in Natick. They MUST be able to get you to a running version or else you have a right to ask for your money back. Tell them that. Ask for a refund and see how fast they help you.