I can´t open some apps like Calibre ot Android File Transfer

What happens when you try?

Launch the Console application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad and start typing the name.

Step 1

For this step, the title of the Console window should be All Messages. If it isn't, select

SYSTEM LOG QUERIES ▹ All Messages

from the log list on the left. If you don't see that list, select

View ▹ Show Log List

from the menu bar at the top of the screen.

In the top right corner of the Console window, there's a search box labeled Filter. Enter the name of the crashed application or process. For example, if Safari crashed, you would enter "Safari" (without the quotes.)

Each message in the log begins with the date and time when it was entered. Select the messages from the time of the last crash, if any. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.

The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.

Please don't indiscriminately dump thousands of lines from the log into this discussion.

Please don't post screenshots of log messages—post the text.

Some private information, such as your name, may appear in the log. Anonymize before posting.

Step 2

In the Console window, select

DIAGNOSTIC AND USAGE INFORMATION ▹ User Diagnostic Reports

(not Diagnostic and Usage Messages) from the log list on the left. There is a disclosure triangle to the left of the list item. If the triangle is pointing to the right, click it so that it points down. You'll see a list of crash reports. The name of each report starts with the name of the process, and ends with ".crash". Select the most recent report related to the process in question. The contents of the report will appear on the right. Use copy and paste to post the entire contents—the text, not a screenshot.

I know the report is long, maybe several hundred lines. Please post all of it anyway.

If you don't see any reports listed, but you know there was a crash, you may have chosen Diagnostic and Usage Messages from the log list. Choose DIAGNOSTIC AND USAGE INFORMATION instead.

In the interest of privacy, I suggest that, before posting, you edit out the “Anonymous UUID,” a long string of letters, numbers, and dashes in the header of the report, if it’s present (it may not be.)

Please don’t post other kinds of diagnostic report—they're very long and rarely helpful.

When you post the log extract or the crash report, you might see an error message on the web page: "You have included content in your post that is not permitted," or "The message contains invalid characters." That's a bug in the forum software. Please post the text on Pastebin, then post a link here to the page you created.

A

"Avast" is the worst of the whole wretched lot of commercial "security" products for the Mac. Not only does it fail to protect you from any real danger, it may send personal data (such as web browsing history and the contents of email messages) back to the developer without your knowledge, give false warnings, destabilize and slow down the computer, expose you to network attack, and corrupt the network settings and the permissions of files in your home folder. Removing it may not repair all the damage.

Some versions of the product also inject advertising into web pages. In short, apart from the fine print in the license agreement, Avast is indistinguishable from malware, and is arguably worse than any known malware now in circulation.

Back up all data, then remove Avast according to the developer's instructions. Restart. Never install any "anti-virus" or "anti-malware" software again.

If you tried to remove Avast by dragging an application to the Trash, you'll have to reinstall it and then follow the instructions linked above.

B

You have not actually installed "calibre." You're running it from the disk image. Download the latest version, then drag the application from the disk image to the Applications folder. Unmount the disk image and delete the DMG file.

C

I can't find Pastebin pages with the information you provided. You have to drag the URL from the search bar of another window into a reply.

If you don't already have a current backup, back up all data, then reinstall the OS.* You don't need to erase the startup volume, and you won't need the backup unless something goes wrong. If the system was upgraded from an older version of OS X, you may need the Apple ID and password you used.

There are ways to back up a computer that isn't fully functional. Ask if you need guidance.

If you installed the Java runtime distributed by Apple and still need it, you'll have to reinstall it. The same goes for Xcode. All other data will be preserved.

*The linked support article refers to OS X 10.10 ("Yosemite"), but the procedure is the same for OS X 10.7 ("Lion") and later.

If you needed Java or Xcode, you would know. You don't need to do anything else.