Why does Matlab keep forgetting my path?

It seems that since around 3 ro 4 years ago, my current installation of matlab seems to regularly forget the directories I have manually added to the path. Several times i have called tech support and they do some chache clearing, path rebuilding and whatnot, and it is fixed. Then a few months later is is broke again. I can keep fixing it, but wondering why. I never had issues in the 20 years prior!

[John D'Errico]

Probably a stupid question here, but a necesary one - do you save the path?

I might wonder if you have a corruption problem on your disk. Have you checked for that?

[John D'Errico]

Please learn to use comments, not answers to make a comment.

"Yes, I do save it. And it seems to take, for a while..."

[Todd Welti]

Right, sorry.

[John D'Errico]

I can only wonder if this is not some sort of a file system interaction problem, as it has not been reported that I know of on Answers as an issue. At least is is clearly some sort of issue between MATLAB and your file system. For example, in the roughly 35 years I've been using MATLAB, I've never seen it happen to me, where the path has been lost.

What OS are you running? Has this problem been present across different MATLAB releases, since you say it has happened for several years?

Next, I wonder if we can pin down what release and OS you were using when it started to happen.

Are you running some other software that periodically goes through your file system, and "cleans" thing up?

[Todd Welti]

I don't remember which version, but I'd say maybe 5 or 6 years ago it started. Never had any issues before that. I'm running W10 now. It is managed by IT, so it has Symantic Endpoint Protection running. not sure if maybe it is doing something. According to my notes, this is what i did to fix it so I could again save the path:

>> restoredefaultpath

>> rehash toolboxcache

>> savepath

[Walter Roberson]

Historically, using the Add-On Explorer to add on files could result in a corrupt path. That would have been fixed a few releases ago, though.

Answer 1

[Andrew Janke]

If I were you, I would give up on setting your path with pathtool or the Matlab GUI (since those try to change the path in the Matlab installation itself) and switch to configuring your path in a user startup.m file. Just stick addpath statements in your startup.m. That'll be more robust and a little "cleaner", since you can share your startup.m between different computers, and it'll work in cases where you don't have write access to the Matlab installation itself.

[Todd Welti]

Good idea! I used to do that many years ago.