mconmay

Q: imac won't stay connected to wireless network

I recently moved and now my imac won't stay connected to my wireless network. Every other device connects just fine, so it's not the service, or the location, because devices are all in the same room.

 

Every time my computer goes to sleep it seems to completely forget how to connect to the internet. There is only one Network (mine) listed in preferred networks. The computer will connect only if I go to System Preferences and run through the Network Diagnostics to tell it exactly what to connect to. Each time it says my connection and internet are fine, which I know.

 

Please someone tell me how to get it to remember my network so I can stop going through the Diagnostics every time I want to use my internet.

iMac (21.5-inch, Late 2013), OS X Yosemite (10.10.2)

Posted on Apr 7, 2015 4:56 AM

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Q: imac won't stay connected to wireless network

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  • by BDAqua,Helpful

    BDAqua BDAqua Apr 8, 2015 9:51 AM in response to mconmay
    Level 10 (123,633 points)
    Apr 8, 2015 9:51 AM in response to mconmay

    Though all of these steps may or may not be needed, I'm including them all.

     

    Make a New Location, Using network locations in Mac OS X ...

     

    http://support.apple.com/kb/HT2712

     

    10.5, 10.6, 10.7 & 10.8…

     

    System Preferences>Network, top of window>Locations>Edit Locations, little plus icon, give it a name.

     

     

    10.5.x/10.6.x/10.7.x/10.8.x instructions...

     

    System Preferences>Network, click on the little gear at the bottom next to the + & - icons, (unlock lock first if locked), choose Set Service Order.

     

    The interface that connects to the Internet should be dragged to the top of the list.

     

    If using Wifi/Airport...

     

    Instead of joining your Network from the list, click the WiFi icon at the top, and click join other network. Fill in everything as needed.

     

    For 10.5/10.6/10.7/10.8, System Preferences>Network, unlock the lock if need be, highlight the Interface you use to connect to Internet, click on the advanced button, click on the DNS tab, click on the little plus icon, then add these numbers...

     

    208.67.222.222

    208.67.220.220

     

    (There may be better or faster DNS numbers in your area, but these should be a good test).

    Click OK.

     

    If that doesn't work try changing channels on your Router.

  • by mconmay,

    mconmay mconmay Apr 8, 2015 9:57 AM in response to BDAqua
    Level 1 (4 points)
    iPhone
    Apr 8, 2015 9:57 AM in response to BDAqua

    Thank you for your suggestion.

     

    I did go through these steps, and added the DNS numbers. I appeared to be able to get online…

    (although it's hard to say because I always eventually get on, the real test is whether I can still connect once the computer has just been asleep)

    I had to undo this, because every website that requires logging in was denying me access to their website, including icloud and gmail.

    Every site I usually use said the connection was not secure and I couldn't go to any of my usual, and important, websites.


    So, back to square one.

  • by BDAqua,

    BDAqua BDAqua Apr 8, 2015 10:03 AM in response to mconmay
    Level 10 (123,633 points)
    Apr 8, 2015 10:03 AM in response to mconmay

    Hmmm, very strange, but you can just change to the old location, none of the new setting will be used.

     

    I have no idea why the security thing, I don't think we changed anything that would affect that!???

  • by mconmay,

    mconmay mconmay May 1, 2015 6:08 PM in response to mconmay
    Level 1 (4 points)
    iPhone
    May 1, 2015 6:08 PM in response to mconmay

    Back to my same problem: imac won't connect to wifi without running diagnostics first

     

    After doing research we found a mac forum that suggested accessing wifi system preferences and locating a few very specific "property list" .plist files. The instructions suggested that we remove those. We did and I was able to connect BUT I always had to first turn wifi off, and then turn wifi on, in order to connect. ***this is always upon waking my computer from sleep, so, everyday***

     

    Now, our internet connection wasn't working, so we had to unplug the router, wait, and plug it back in. Fine, that happens.

    Everything connects now, except my computer.

    Now, I'm back to my original problem again. imac won't connect to wifi without running diagnostics first.

    So unplugging the router somehow undid what we removed from the "property list".

     

    This is extremely frustrating.

    The internet connection is fine.

    The router is fine.

    My computer, specifically, has a problem staying connected to a network. Anyone?

  • by BS2too,

    BS2too BS2too Sep 29, 2015 3:15 PM in response to mconmay
    Level 1 (0 points)
    Sep 29, 2015 3:15 PM in response to mconmay

    Sorry to resurrect this, but I have the same problem with my Macbook Pro but only on my home network.  I can connect but it drops frequently.  I have to run the diagnostics to reconnect.  It is beyond annoying... I can't work on anything important at home.

     

    Suggestions?

  • by BobHarris,

    BobHarris BobHarris Sep 29, 2015 5:43 PM in response to BS2too
    Level 6 (19,420 points)
    Mac OS X
    Sep 29, 2015 5:43 PM in response to BS2too

    BS2too wrote:

     

    Sorry to resurrect this, but I have the same problem with my Macbook Pro but only on my home network.  I can connect but it drops frequently.  I have to run the diagnostics to reconnect.  It is beyond annoying... I can't work on anything important at home.

     

    Suggestions?

    Then I suggest you start looking at your home network equipment.

  • by Azer1967,

    Azer1967 Azer1967 Nov 25, 2015 2:11 AM in response to BS2too
    Level 1 (0 points)
    Nov 25, 2015 2:11 AM in response to BS2too

    I hear you, I have the same problem, I even got new router, tried to disconnect all other devices from my network (4 Iphones, 2 Ipads, Apple tv, 1 PC, 2 mac b pro's, 2 mac books. So now my pro is the only thing running, and then it works (slightly better) ) however, this is not acceptable and I can't work from home...

     

    Some times it says that there is a IP conflict? But not always...

     

    Just to try, I connected a VPN software, and now it works perfect (with the VPN) but thats not what I want nor is that the purpose of VPN? I don't know what to do. When I was using PC I could always find a solution to all my problems, but MAC is user friendly when it works...

     

    good luck

  • by BobHarris,

    BobHarris BobHarris Nov 25, 2015 6:18 AM in response to Azer1967
    Level 6 (19,420 points)
    Mac OS X
    Nov 25, 2015 6:18 AM in response to Azer1967

    Azer1967 wrote:

     

    ...I even got new router, tried to disconnect all other devices from my network (4 Iphones, 2 Ipads, Apple tv, 1 PC, 2 mac b pro's, 2 mac books. So now my pro is the only thing running, and then it works (slightly better) ) however, this is not acceptable and I can't work from home...

     

    Some times it says that there is a IP conflict? But not always...

     

    Just to try, I connected a VPN software, and now it works perfect (with the VPN) but thats not what I want nor is that the purpose of VPN? I don't know what to do. When I was using PC I could always find a solution to all my problems, but MAC is user friendly when it works...

    Are you really on Leopard 10.5, or are you just pigging backing on this thread?  With all those Apple devices, I find it hard to believe you are really still using Leopard 10.5

     

    First do you have a WiFi password setup?  Or another way to put it, is it possible you have neighbors that are pigging backing on your home network?  Conflicting IP address is generally only something that comes from other devices using the same router, but not letting the router assign the IP address.  A device with a fixed IP address that happens to be in the same range as the DHCP addresses the router is assigning.

     

    You could try assigning your troubled Mac a DHCP Client ID.  Most routers will give a device with a DHCP Client ID the same IP address each time it connects.  System Preferences -> Network -> Advanced -> TCP/IP -> DHCP Client ID.  Make it unique but keep it simple with just letters and numbers.

     

    Some routers allow you to configure them to always assign the same IP address to a given device as well.  Hopefully this would prevent IP address conflicts.

     

    I cannot image why using a VPN would keep your connection stable, except that once the VPN is established, your Mac will no longer talk to anything on the local network.  It will stop using the router for DNS lookups, it will stop talking to your other devices, etc...  Also various services that phone home or keep a connection to a server will most likely be blocked by the VPN service.  For example a messaging client, Skype, the Mac checking for software updates, etc...   Many of these activities are blocked by a VPN depending on how the remote VPN server is configured and the network you are joining via the VPN.

     

    You could try giving your Mac its own DNS servers to use, that would at least eliminate one source of asking the router for assistants.  System Preferences -> Network -> Advanced -> DNS -> [+]

    OpenDNS.com:

    208.67.222.222

    208.67.220.220

    Google:

    8.8.8.8

    8.8.4.4

    The first one you choose it the one that will be used most of the time.  The 2nd will be a fall back if the first does not respond in a timely manor.

     

    Do you have USB3 devices?  A poorly shielded USB3 cable or USB3 enclosure can generate interference at the same frequencies used by WiFi.  A USB3 device located close to the router or close to your Mac can cause problems.  NOTE:  It is NOT all USB3, just ones that did not do a good job of shielding their electronics and cables.

     

    Other things to try (this is just throwing things out)

    Purge all Preferred WiFi networks, except the ones you really use

    And then drag the home network to the top of the preferred list

    System Preferences -> Network -> Advanced -> Wi-Fi -> Preferred networks -> [-]

     

    Make sure your router's time is the same as your Mac (and the rest of your timezone as well).  There have been reported issues of protocol problems when the router and the Mac think they are hours apart.

     

    Have you tried creating a new Network Location?

    System Preferences -> Network -> Location -> Edit Locations... -> [+]

    Then populate the left side with networking interfaces via the [+] button

     

    Have you tried deleting your networking preferences and starting from scratch?

    Finder -> Go -> Go to Folder -> /Library/Preferences/SystemConfiguration

    com.apple.airport.preferences.plist (or just rename it)

     

    Are you connecting via 2.4GHz or 5GHz radios?

    Hold Option key and click on the WiFi menu bar icon

    It should show you more details about your WiFi connection.  If the channel number is 1-11 (13 is some countries), then you are 2.4GHz.  If channel 36 or higher, then 5GHz).

    Can you switch to the other radio by configuring your home router to use different SSID names for the 2 radios?  Then again, does your router have 5GHz radios?

     

    It is possible that you have interference from your own home devices or neighbors.  It could be from competing WiFi routers using the same channels, or it could be from baby monitors, cordless phones, microwave ovens.

     

    You can check for competing wifi routers and interference if you have something newer than Leopard (maybe one of your other Macs).  Hold the Option key -> Click on WiFi menu bar -> Open Wireless Diagnostics -> Window -> Utilities -> Wi-Fi Scan

    You want to identify your network and see from your Macs location the RSSI.  -30's would be great.  -40's and -50 would be good too.  -60's and higher not so wonderful.

    Then you want to look at the competing WiFi signals from neighbors.  If they are on the same channel or for 2.4GHz within 5 channels of you, then they can be interfering. But it is their signal strength that matters.  If they have -60's -70's, -80's, and you have much stronger -30's, -40's, then chances are they are not a problem.  But if they are stronger than you, that is a problem if they are sharing the same channels.

     

    Also look at your Noise.  It should be -90's.  If you are getting -80's you can live, but it does indicate interference is happening.  Get -70's, -60's or worse, and you have serious radio interference.