Lost whole folder after updating El Capitan

Try using Spotlight search to find it. Search for a file you know is in the folder.

Sometimes glitches happen. In that case restore the file from a backup.

londonyblue wrote:

Hello,

I have updated to El Capitan last night. Now I realized that the Whole folder which I store all my stuff. I had the folder under "Macintosh HD">"system". Now its not there anymore. Where should I find it? Oh its just lost.....please help!!!thank you!!!!

Why did you "store all my stuff" i n the System folder? The System folder is not a good place to store data, as you determined. Your user folder is a better place to store data.

So there was some local data stored in a directory named /System, or in a folder under /System? That's a directory that is used by and reserved to OS X AFAIK — user files are normally stored under the /Users directory. Apple has some expectations of where files are stored on OS X. Those other contents within /System have unfortunately probably been removed as a consequence of the upgrade, and as a consequence of the System Integrity Protections. Roll in your backups.

I'll ask again, why did you do that rather than storing your data under your user folder?

Re: Missing Documents after El Capitan Upgrade

londonyblue wrote:

yeah I store it in a folder I created under /System. I guess its all gone now. Which is sad...

Apparently the old stuff is in /Library/SystemMigration, but — without backups — it'll be gone sooner or later. Please: please get backups going. Answering the "I lost my {irreplaceable files}" isn't any fun for anybody, and computers inevitably fail, some get stolen or damaged, and apps and upgrades can and occasionally fail, and commands are sometimes mis-entered, and some nasty folks have been encrypting and ransoming computer data.