Sharing my computer, but want to lock everything down but one file. How?

December 28, 2015 1:57 PM

I need to share my computer with someone for a few weeks while we work together on a pair project in excel. But I want to lock everything else down on my computer so they can't open/copy/email my other files if I step out of the room; or so they can't open my browser and read my email / see my history, etc.

We will be working on a single excel spreadsheet, so I need to password protect/lock everything that isn't that one file; ie. (1) Files (some on desktop, some on hard drives, some on dropbox (2) Internal Hard drives (3) Dropbox (which is on my desktop) (4) browser (I use firefox). How do I do this? Also, is there anything else I need to think about re: safety and security as I share my computer with someone (who I don't know at all) for up to a month?

Thanks!

posted by tangyraspberry to Computers & Internet (10 answers total)

What operating system do you use? This could probably be achieved in OS X by creating a new user and restricting all access using the users panel.
posted by Hermione Granger at 1:59 PM on December 28, 2015 [2 favorites]

The best way is to make a second user account and created a shared folder for the accounts.

How to Share Files Between User Accounts in Linux, Windows, and OSX.
posted by The Deej at 2:01 PM on December 28, 2015 [3 favorites]

Have you looked at Excel Online? You basically run Excel in your browser so you don't need to think about local security.
posted by Foci for Analysis at 2:01 PM on December 28, 2015 [3 favorites]

You could do the same thing under windows by creating a limited account and give it access only to the excel file.

However do they not have a computer? Because if you both have a windows machine you could share just the file over with windows sharing and they'd never have to sit at your machine at all.
posted by Mitheral at 2:03 PM on December 28, 2015 [1 favorite]

It might be even easier to just create a new user and associate the user with a new Dropbox account, and then share a folder with that file in it with the new Dropbox account.
posted by rockindata at 2:25 PM on December 28, 2015 [2 favorites]

Just wanted to voice support for the other people recommending another account: if you have to let an untrusted user on a computer, that's the only remotely safe option. I'd use something (network storage, USB drive, etc.) to transfer the files back so it always happens under your control at the time of your choosing. If you're really concerned, you might want to use OS X's File Vault or Windows’ encrypted folder support to protect your primary account or sensitive data from malice or poor decisions malware decisions.

Dropbox is the main sticking point since many people tend to have most of their life stored there. You could use selective sync but anyone with access to the computer could always disable that. I'd second rockindata's suggestion: ensure that they have an account and use that so the only files available are again the ones you intentionally share.
posted by adamsc at 4:19 PM on December 28, 2015

For a month, I would definitely find it worthwhile to buy an extra cheap laptop and just do file sharing between the two computers, without giving the other person direct access to yours.
posted by ktkt at 5:29 PM on December 28, 2015 [1 favorite]

Another thing is that there are older unused laptops with excel on them all. over. the. place. Most middle class houses have at least one in a closet somewhere. It might only work plugged in, and weigh 10 pounds, but it'll run win7 and excel just fine, especially after a clean install. Ask around, you will almost certainly find one in your social circle that someone would be happy to be rid of.
posted by rockindata at 5:39 PM on December 28, 2015 [1 favorite]

Google Sheets or Excel on-line.
posted by jeffamaphone at 8:13 PM on December 28, 2015

This is exactly what separate user accounts are for.

Go to Control Panel -> User Accounts, add passwords to all your existing accounts (there will probably be only one), then create a new Limited User account that you will use while you're sharing your computer with your collaborator. Don't create another Computer Administrator account by mistake.

As long as you haven't ever gone out of your way to save stuff to unusual locations on your internal drive, everything personal that already exists on your computer will be inaccessible via the new user account. After creating it, you should log on as the new user, think like a snoop, and poke around trying to get access to stuff you'd rather other people didn't see. I expect you'll be pleased at how little you can dig out.

Software, like Excel, is available to all user accounts, so you won't need to reinstall it just because you now have more than one. Browser extensions (Adblock Plus and so on) will need installing into the new account's browsers, because they're part of the individual account's browser profile. Dropbox folders are also per-user-account; your existing one won't be accessible from the new account unless you log in from there using your existing Dropbox username (email address), so don't do that.

Unplug all your external hard drives and put them away. Most hard drives come pre-formatted with a filesystem that has no support for account restrictions, and most people don't reformat them with a filesystem that does, so everything on your external drives is likely to be as accessible from the new account as it is from your existing one.
posted by flabdablet at 3:52 AM on December 29, 2015