High Sierra and Bootcamp - issue after WIndows 10 partition size change

[activestate]

Recently i have installed High Sierra and Windows 10. I have 250gb SSD drive that i found is badly sliced (too much space for win10). So i've used EaseUS Partition Master to reduce windows partition. After my change and reboot, i've noticed that OSX is not starting by default, but windows started by default. So i've rebooted mac again, with OPTION button pressed. Then, list of available systems appeared, but only windows can be selected, OSX is there no more. Please, can anybody tell me if there is any way to start OSX again ? Windows 10 sees this partition but i have no idea if it's formatted or not , i have no idea what happened. Thank you.

EDIT: Do you think this solution will fix my issue ? "Can try reinstalling Mac OS X on your Mac partition, you shouldn't lose your data it will just install the OS back on the hard drive, you will be able to keep your Windows Partition, this will work but it depends on how damaged your system partition was, so make sure you have a backup of your data. Then give it a try. " https://discussions.apple.com/thread/3571327

PS: This is what i see on repair tool.

 

[Velin]

In Windows 10, do you see the "Bootcamp" icon in the lower right-hand corner? If so, see if you can select OSX to be the default on a reboot, or if the Bootcamp icon will simply allow you to force a reboot or restart into OSX. If you don't see that Bootcamp icon, download and install Bootcamp drivers. Also, review this. This may be one way around your inability to select an OSX boot drive from the Startup Manager.

Also, be sure and try the Option key from a cold reboot, that is, totally power down your computer, then press the power button plus the Option key. This is unlikely to make a difference, but a single attempt will cost you about 30 seconds of time.

If these things fail, you may also try resetting NVRAM. This also is unlikely to fix the issue -- but it too is worth a single attempt.

One thing that is worrying is, I see only a Bootcamp/Windows partition on your SSD with the Repair Tool view. That could spell bad news, unfortunately, because under your SSD, there absolutely should be both Bootcamp and the name you gave your OSX partition. (Or an OSX container if you're using the brand new APFS file system.)

 

[activestate]

Hi @Velin,
Thank you for the reply.
I've tried those solutions, all the time OSX didn't see this partition : "That could spell bad news" - yes indeed.
I had to buy isoftboys recovery tool, grab the data (this soft was seeing my partition witout any troubles !), copy into external drive and format whole drive and copy back this what was important for me... So no luck with partition repairing.
Cheers !