El Capitan won't Boot after update

OK reading thru the whole thread and did not find any solutions.

I had in stalled el capitan and face this problem fortunately i had a time machine backup before the upgrade so i reverted back to yosemite.

I have the late 2104 15 Macbook pro retina.

My question now is how can i upgrade to el capitan with out having this problem.

I dont mind installing el capitan brand new and then installing the sofwares i use again.

The main worry for me is Apple mail I need those mail safely back and the rules.

And a few other softwares which i think i can manage to get back.

Alternatively i am posting herewith my extention list can someone identify which could be the culprit to the problem so i could simple remove them and not have to go thru the above.

Vik

I have seen tap/tun and BoomDevice cause problems, but I don't know if they would prevent booting.

LittleSnitch has also caused some issues, but I don't think they were related to crashing or no boot.

I don't know what kilf, kinke, or the overdrive stuff is.

The rest are installed by Apple.

Thank you Barney for your prompt reply

I did some google search and apparently

1 KLif is related to kaspersky ( i dont have kaspersky installed) would it be safe to delete in this case?

2 Klnke is also related to kaspersky ( i dont have kaspersky installed) would it be safe to delete in this case?

3 What software us TAP/TUN related to so i can simply remove these application before upgrading.

4 Will remove BOOMDEVICE

5 Will remove little snitch.

6 No idea what overriseappleusbcdc.kext and the similar name ones are ( what happens is i remove them ?)

I Do have avast Av installed which i will remove before upgrade. is there anything else i need to be careful with?

Vik

Hi, this comment is only for people who has two monitors: keep both monitors on during the restart!

I left only one monitor on during the restart operation and after a couple of minutes the apple logo and the status bar disappeared leaving the screen blank. After a few minutes, I thought my desktop computers was stuck, so I switched it off/on and got the same results. Then, just by intuition, I turned the second monitor on and discovered that the apple logo and the status bar just switched to the second monitor leaving the first screen blank.

Of course, this may not be the case of other users, but take it into consideration before trying something else since the screen may look similar to the problem described in this trend.

Thanks Carlos. Your tip enabled me to restart my MacBook and from there I was able to go through Finder to the Library and remove all the suspect .kext files. I am pretty sure the culprit was Eltima?? but I also removed several other really old ones. However every time I restarted my MacBook, Safari would automatically open to a Help page which was written in Vietnamese. After lots of searching I eventually went through System Preferences, User, and Login and removed every single Login item. At last, I have El Capitan running smoothly on my MacBook. Cheers!

Hi luxnova ,

thanks a lot !!!!!! Lifesaver, it actually worked. The repair shop only told me something cryptic about my harddrive (SSD) being defect, slowly deleting itself and wanted 200 € for sorting it out. I plainly told them their explanation didn't seem very plausible and took thinks in my own hand, I can be very stubborn. So thx to you and this community who saved me 200 € and a lot of trouble

SO pleased you no longer have the problem, but I do!

I Can't see where to ask further questions...I'm now on an iPad mini and the screen isn't designed to fit so navigating the site is a bit of a nightmare:/

I Do have an up to date time capsule but how can I access it when the MacBook won't boot.? I have no other apple device

cheers

Are you able to boot in recovery? Make sure your mac is powered off. Press the power button and immediately you hear the start up chime hold down the Command and R keys together until the Apple logo appears. Sometimes it takes a few seconds longer to start booting in recovery, and often seems to stop then start again part way through. Once you are in Recovery mode there are a few options you can make to get your Mac going again. At one point I restarted from a backup from an external backup and from there was able to get things moving again. One of the other choices at Recovery is to re download OS X . This takes some time, but if you do go that way save the installer when it has downloaded onto a USB so you don't have to download it again. Good luck.

Have you tried to boot in recovery mode lice MacBook56 advised. Should work...once booted in recovery mode you have several options. Either reinstall El Capitan (if you have a Wireless connection) or restart from your backup, this enables you to switch back to Yosemite.

Hope you can sort it out. Good luck.

TThank you - I have opened in recovery; the time capsule showed but it wont let me in 'there was a problem connecting to the server' advising me to contact the admin....this is just a household?? What is it requiring me to do?

...forgot to say that with the error msg that beach ball is still spinning??

When you boot in recovery the wifi doesn't turn on automatically. Go to your wireless icon at the top of your screen and reconnect to your home wireless. Then try again. Sometimes you just have to do the same things over a couple of times before they work. Who knows why!

Yo People,

I have gone through all of the recommended steps. This includes resetting PR, etc. I have not re-installed the OS; because, I upgraded to El Capitan by downloading the installation dmg from apple. There is no way for me to reinstall without getting to my internal drive (standard MacBook Pro SSD that came with the machine). Reboot attempt with option key down displays the Boot Well USB and the internal drive. When the internal drive is selected, the machine hangs with a black screen, the Apple logo and no bar movement.

However, I have been able to boot using Drive Genius Boot Well. This utility sees the internal hard drive. All of the diagnostics show there nothing wrong with the internal drive.

When I attempt to restart holding the option key down, the internal drive and Boot Well show up. If internal drive is selected, black screen and computer hangs. If I restart with no Boot Well USB, same thing happens after choosing internal drive. Black screen and machine hangs. Normal boot also black screen and machine hangs.

Obviously, without the ability to get the machine up to the desk top, I cannot do terminal commands or anything else.

At this point, I have done all that has been suggested, but no joy.

One of the last things I want to do is take my machine to the Apple store in Providence. The guys are useless. Totally.

Frankly, it is amazing to me that Apple has not sent out an emergency update of El Capitan.

If anyone has suggestions at this point, I would really appreciate hearing them.

Thanks

Frankly, it is amazing to me that Apple has not sent out an emergency update of El Capitan.

If anyone has suggestions at this point, I would really appreciate hearing them.

There isn't anything wrong with El Capitan. You most likely have some incompatible third-party software installed. Some of the Anti-virus packages will prevent booting, and I think SyncMate will also prevent booting.

Can an you boot to Safe Mode? Try safe mode if your Mac doesn't finish starting up - Apple Support

Saying that some third party app may be causing the problem, but it is not particularly useful in my case. I have about 100 apps on my mating.

If third party apps are responsible for the black screen boot problem in El Capitan, then it is reasonable to think that someone at Apple is on top of this.

If so, then that person or one of his or her people needs to publish a list of those apps ASAP. Like ASAP!