how do i check for virus or adware on my mac, and then remove them

Follow the instructions on this web page in order to manually remove adware from your mac: https://support.apple.com/en-us/HT203987

You may also find adware removal guide on this page http://www.thesafemac.com/arg-identification/

If you do not want to remove adware manually use adware medic tool in order to scan and remove it(probably the easiest way): http://www.adwaremedic.com/

Download, open adwaremedic dmg file , and run it by clicking “Scan for Adware” button to remove adware.

Once done, quit AdwareMedic and restart your mac.

There is no need to download anything to solve this problem. You installed a variant of the "InstallMac" trojan. Take the steps below to disable it.

The criminal behind this attack tries to make the malware hard to remove by varying the names of the files it installs. This procedure works as of now, as far as I know. It may not work in the future. Anyone finding this comment a few days or more after it was posted should look for a more recent discussion, or start a new one.

Back up all data before continuing.

1. Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination command-C:

~/Library/LaunchAgents

In the Finder, select

Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return. A folder named "LaunchAgents" will open.

2. Inside the folder you just opened, there may files with a name of the form

something.download.plist

something.ltvbit.plist

something.update.plist

where something is usually a meaningless string, such as "InKeepr," "Listchack," "Oliverto," or "Texiday." It could be anything. The point is that the same string will appear in the name of three files.

You could have more than one copy of the malware, with different values of something.

Move all such items to the Trash. There may not be any other files in the LaunchAgents folder; in that case, you can delete the folder, but otherwise don't delete it. Other files in the folder are not necessarily malicious (though they could be, if you also installed some other kind of malware.)

Log out or restart the computer. The trojan will now be inactive, but there are a few more components of it that should be cleaned up.

3. Open this folder in the same way as above:

~/Library/Application Support

and move to the Trash any subfolders named with the same something you found in Step 2.

Don't move the Application Support folder or anything else inside it.

4. Open the Applications folder. If there is an item with the same name as in Step 3, or any of the other names listed in Step 2, drag it to the Trash.

If in doubt, press the key combination option-command-4 to arrange the apps by date added. Look at the apps that have been added since you first noticed the problem. If there is one you don't recognize, drag it to the Trash.

Empty the Trash.

If you get an alert that the application is in use, force it to quit.

5. From the Safari menu bar, select

Safari ▹ Preferences... ▹ Extensions

Uninstall all extensions you don't know you need. If in doubt, remove all of them. None is required for normal operation. Do the equivalent in the Chrome and Firefox browsers, if you use either of those.

6. Reset the home page in each of your browsers, if it was changed. In Safari, first load the home page you want, then select

Safari ▹ Preferences... ▹ General

and click

Set to Current Page

Thanks so much for the detailed description!

Cheers, Goeknur

Helped perfectly. Thanks a lot for writing that out.