Macbook WiFi Sketchy After Upgrade to 10.9

I have a Macbook 13" Late 2009.  I installed a 240GB SanDisk II SSD.  Installed 10.9.  The computer works great with the exception of the WiFi.  Problem is sometimes it will work and other times won't.  Some networks when I attempt to connect I'm prompted to enter the password but after doing so I'm told its incorrect.  Other than this problem the computer works flawlessly.  Thanks in advance.
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Go to Network Prefs>Advanced>Wifi  and delete the networks that are giving you problems and try again.

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It might be bluetooth.

If or when you upgrade to Yosemite, there may be more problems with Wifi and Bluetooth.
1namylnAuthor Commented:
I will try this.  The machine should be back in today.  I have no plans to upgrade this device to 10.10.
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1namylnAuthor Commented:
Strung, deleted the networks.

Serial, removed the bluetooth file.

Won't know if these issues are resolved until the customer gets home.  No issues with the wireless at my location.  Fingers crossed...
1namylnAuthor Commented:
This didn't fix the issue customer reports.

They were able to reconnect to the network and use it properly. The lid was closed and when the lid was reopened they were unable to connect. They claim when they move closer to the modem the system reconnected again.

My first thoughts are that after coming out of sleep mode it simply takes a few moments to reinitialize. However I didn't have the same problem at my office.
If they had to move closer to the modem to reconnect, then they presumably were at the edge of the usable range of the modem.
1namylnAuthor Commented:
The claim is it worked fine before the upgrade...

They stated that when clicking on the wireless icon after sleep it stated to move closer to the modem.
1namylnAuthor Commented:
Current version of the Mac's OS is 10.9.5
Well, they have been reducing the power on the Wifi to extend battery life in Yosemite.  I wonder if they backported some of that to Mavericks.

Maybe a reset of the SMC and PRAM might help.
1namylnAuthor Commented:
No luck with resetting SMC or PRAM.  What about 10.8?  Seems like rolling back might be the best option.  Well not rolling back but a new reinstall with an older OS.  I can go back to 10.7 if needed but would rather stay as new as possible.
Kyle SantosQuality AssuranceCommented:
1. Does the customer have a Netgear router? could be a similar issue you're seeing now.

2. Does the customer have a dual band router?  Can they switch to a 5ghz frequency?  A lot a wireless woes have been fixed by getting off the congested 2.4ghz frequencies (nearly everyone is still using this frequency).  I recently turned on my router's 5ghz frequency on my Airport Extreme for my macbook pro.  I was having intermittent connection issues and my ISP told me I should change my router's channel (nearby routers were also using channel 6 in my situation) or start using the 5ghz frequency.   I did both and things are fine now.  My macbook has the latest osx and version.
1namylnAuthor Commented:
No Netgear router.  Does the same thing on multiple routers and router OS's.  These problems only occurred after a clean installation to OS 10.9
1namylnAuthor Commented:
I have performed a clean install of 10.7 and when the lid is closed then reopen the connection only re-connects if I'm very close to the router.
1namylnAuthor Commented:
Going to try a USB Wifi and see if issues persists.  Thoughts?
Kyle SantosQuality AssuranceCommented:
I  would like to know what router and model the customer is on.  And is there an option to try a different router?
1namylnAuthor Commented:
Comtrend, Linksys and buffalo. Some are dual band some aren't.
Kyle SantosQuality AssuranceCommented:
Post-sleep mode may be conflicting because I had a similar issue when I upgraded my macbook from Mavericks to Yosemite.  Can you go to System Preferences > Security and unchecked the 'require password' box.   Then put the macbook in sleep mode, close the lid and then see if the same issue persists?
1namylnAuthor Commented:
I'm awaiting a USB wifi card.  I'll update ASAP.
1namylnAuthor Commented:
USB card works with no problem specifically when the machine is brought out of sleep mode.  That said it doesn't have the range of the other.  Customer has decided to purchase a more up-to-date machine.  Points are for your efforts.
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