10.13 High Sierra Wi-fi issue

I have fixed this issue in early-2015 Macbook Pro by changing the host name (SSID) of my Wifi Repeater/Extender. Before this, my Macbook randomly on & off wifi or sometimes won't connected at all, and I had Wifi Router and Repeater with a same host name. I hope this help. 🙂

Have you tried monitoring your network through wifi diagnostics?

Have you checked through Airport Utility to see if there any updates?

Have you tried removing NETWORKS previously connected (a hassle yes) but will often resolve the issue.

5Ghz: Dragging it to the top should help you even adding back other networks.

DO NOT HIDE the network.

Router should be configured to 802.11a/n & if thats causing issues then try just the 'n'

Click Advanced and go to DNS settings and make sure Googles two are on top: 8.8.8.8 & 8.8.4.4

You may need to set manual MTU to 1453

20 or ""40 MHz

"You may need to change your 5Ghz channel from AUTO to 40, 41, 44 or 48; as an alternative.

Check if you don't know your current channel from wifi icon by holding OPTION while clicking.

Recommended settings for Wi-Fi routers and access points - Apple Support

It's not a total fix and some times you have to monkey around with turning airport on and off until you get a connection, but for those who have no ability to change network name or lower or raise the power to whichever network to boost it's dominance --- this string in terminal can help.... you SOMETIMES like I said may have to power off and on the wifi on the laptop but when you get a Solid 5G connection which can be viewed with Option & wifi symbol it works for awhile, some times for hours or days, and other times it switches back to 2.4 and you'll have to do it again, but for me and all of my macbooks and mac pro, macbook pro, etc - this has helped me:

/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airp ort prefs joinMode=Strongest

I had the same problem. At any time after you got your new iMac did you reset your router to factory settings (the paper clip thing in the Reset hole, hold 2 seconds) and then change the network name and password to what you want through the web admin interface? That was a great help to me.

This was very helpful. Connected to 2.4 instead of 5 and it seems to be working much much better. Definitely a bug.

just change your wi-fi password on your router, i have solve this problem right now!!

seem situation on latest 2013 MBP

It's running smoother for sure.

It did reset a few settings for me, but is freshly upgraded (awhile to do) and so far so good:

macOS High Sierra 10.13.2 Combo Update

Just found this out after moving over to High Sierra. No problems connecting with IOS devices, but with my MBP it will not automatically detect and connect to my home WIFI until I re-enable SSID broadcast. An official fix for this from Apple is urgently required.

Since you don't get it.

Here

Installed CLEAN High Sierra on empty HD, Wi-Fi fails to connect to hidden networks at login. It can't even remember previously saved connections

Installed Mac High Sierra over Sierra, Same Result as clean install

Installed CLEAN Sierra, Wi-Fi Connects with no problem to Hidden Network, did another upgrade to High Sierra and it fails again.

Installed El Captain and upgraded to Sierra, then High Sierra, Wi-Fi works just fine on EVERY SINGLE OS EXCEPT FOR HIGH SIERRA.

<Edited by Host>

Assuming it's the 5Ghz?

For the performance, changing the wifi key seems to fix that (thanks Mac_slide). It makes 0 sense but it seemed to do the trick.

The only way I can get connection to my 5Ghz to work is to remove all "preferred Networks" from settings. Power off (not restart) the Mac. Then it will connect when I power back up. If I connect to another wifi network/hotspot, it will not re-connect to the 5Ghz. I have to make sure I have no other Preferred networks then power off and then power back on again.

smh

That's what I had to do: completely start over and reconfigure the router, but it worked and has been good for a couple of weeks now. I believe the original poster said his/her ISP didn't "allow" any tinkering with router settings. That's like not being able to edit your own php.ini file. Time for a less paternalistic ISP.

There is a supplemental update to 10.13.2. It may be related to the intel problem, but may be it also resolves the wifi issue.

Similar problem here on iMac 27" (mid2010). Vintage, but still performing i7-16GB machine.

WiFi doesn't automatically connect anymore trusted networks after upgrading to High Sierra.

Tested many work-around procedures (turned off/on WiFi card, tried on different routers, changed SSID of router/s, changed from 5GHz to 2.4GHz band on router, reset MSP on iMac, reset NVRAM on iMac, deleted WiFi settings folder on iMac, reinstalled WiFi card on iMac, clean installation of High Sierra onto an external usb drive, and much more..) but nothing solving.

Also found/installed a clean "El Capitan" OS version onto an external usb drive, the problem disappeared, so clearly not a problem on network card.

Currently in touch with Apple experts to find a suitable solution (OS side ?).

Just in case it helps someone, YMMV... Had the same issue this morning...

High Sierra 10.13, MacBook touch bar.

Wifi won't hook up, sees network, but stays in search mode. Moved closer to the router, inside the house, wifi connected after a minute or so.

Now happily back on the deck... This was not issue before update to 10.13.