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Microcell won't stay up more than a few minutes


Microcell won't stay up more than a few minutes

I have been trying to resolve this problem but it seems I'm getting the run around, trying to find out if anyone has had a similar problem and how they got it fixed.


We have had internet issues but they were recently resolved so our speed is well above what is needed to keep the microcell connected. We also have it plugged in directly to our Westell 7500 modem/router and it is set up per AT&T instructions for that model.


The woman I spoke to yesterday said that my address was not matching (was 300 meters difference) where it was coming up and the street was wrong that she told me (since all the street names are similar and we live in new construction I run into this sometimes) so she suggested I 'add a new microcell location' and I did with the alternate spelling of our road that sometimes systems default to and I re-activated. She said she thought this was our problem since it is really only accurate to a few meters so it wouldn't work right. I don't know if this is true, but I figured I'd try it cause it might work. She also told me it could take up to 24 hours to get a GPS lock. The thing is, the GPS light isn't what is flashing periodically, it is the 3G light.


Everything activated fine, but every few minutes throughout the whole day the 3G light flashes and we lose the microcell connection. Same problem we've always been having. It seems like it doesn't happen at night, but I'm not staring at it while I sleep, so I don't really know. I can't use this thing at all and it's really annoying cause when you're not on it and it comes up, sometimes I lose the call, and when I'm on it and it goes down I lose the call. I can't talk for more than 5 minutes at a time.  I plan on calling AT&T back to see what the next step is or if the address I put in this time is more accurate.


Any suggestions would be appreciated. We live close to the woods and have very poor cell signal. We have no problem with our VOIP phones so this shouldn't be disconnecting so often. Help!

Message 1 of 10

Re: Microcell won't stay up more than a few minutes

Friday's call to AT&T had me updating my address. Did not fix the problem.



Today's answer was that my jitter is too high and has to be under 5 ms for the Microcell to work properly. I am sitting here with they guy on the phone testing it and my microcell is up and my jitter is very high (like 48) so I don't believe him. Was using a VOIP phone and still Microcell didn't go down. Tested after off the call and jitter still in the same range and it still hasn't gone down (but it will). Ha! Just tested jitter at 5. Now at 88ms, Microcell still up, so I don't think this is the issue.


Anyway, next step he said was to de-activate and re-activate and if that doesn't work to take it to an AT&T store and switch it out. I still don't think this will solve the problem since I've seen people with Westell 7500 modems with similar problems. Someone who has a 7500 westell that it works on, please help!

Message 2 of 10

Re: Microcell won't stay up more than a few minutes

So, I had gone into my modem settings before I talked to AT&T last, I don't know what I did, but I must have started everything up in the proper order, so then I talked to ATT as I said in the last post, they did nothing, and my microcell stayed up the whole time I talked to him, so I figured, leave well enough alone. It stayed up for the past whole week! Then my power went out last night. now it won't stay connected again. Tried going back into modem settings, which I know sounds stupid, but it's the only thing I did the last time that got it to stay up.  3G light wouldn't go solid at all, restarting again. What is the proper order for starting this all up?

Message 3 of 10

Re: Microcell won't stay up more than a few minutes

Your Micro Cell could be defective.  Call 611 and insist on speaking with a supervisor in the Micro Cell dept.  Tell the 1st CSA you tried talking to the techs but they have no formal training in electronics.  Apparently anyone who can read can be a tech at AT&T.  No lead person either but only a supervisor.  They are the ones who will really troubleshoot your device.  Believe me I went round and round with AT&T about the very same subject.  The warranty dept. sent me a new one and I have to ship back the defective one.  Mine would not hold a 3G signal so I kept getting dropped calls, the thing was useless.  It was a pain to activate and get working, would not lock on to 3G signal, no bars no sevice, it seems to be working now though.  I hope it continues that way.  If not AT&T will be getting sued.  I feel there is no reason for such deplorable service in such a large metropolitan area such as Phoenix AZ.

Message 4 of 10

Re: Microcell won't stay up more than a few minutes

Well, I'm almost sure it's not defective. Based on the things everyone has said here in the forums, they send them back, get a new one and it does the same thing. I bet there's a giant landfill somewhere full of these things (or they just re-package them and send them on to the next guy). Anyway, AT&T's latest recommendation to me is that my line attenuation is too high and I have to contact my ISP. It is too high, but it's doubtful they can improve anything because of where I live.


If this really were the case, why did I get the thing to work for a solid week? And how do I do that again? Has anyone gotten their Microcell to work with a Westell 7500 Modem Router with any success? (That didn't have to plug it in to something else) And what is the proper start-up order, because I think that's how I got it to work for that week straight. I wish my power hadn't gone out!

Message 5 of 10

Re: Microcell won't stay up more than a few minutes

Oh, and is there any point to de-activating and re-activating it like they suggest?
Message 6 of 10

Re: Microcell won't stay up more than a few minutes

Every time you call AT&T, you will get a different answer. They don't care whether or not they solve the problem so long ad they get you off the phone. Their favorite move is to close your ticket without calling back.

"Line attenuation" is a characteristic of DSL lines and it's silly that someone diagnosing the Microcell would say that it in any way explains its behavior.

If your Internet connection has excessive jitter, then you might try replacing the modem and/or router. If you go down this road, my advice is to get separate ones rather than an integrated model. This allows you to get best-of-breed models for both functions rather than potentially compromise. It also allows you to attempt "priority mode" configuration of the Microcell, assuming your service does not use PPPoE.

Make sure your DSL modem is configured to be a dumb bridge. Don't let it be the PPPoE end point. Have it pass that job to your router. You want to make sure your router has good QoS capabilities if you don't use "priority mode". Make sure you set it up to give your Microcell first shot at the uplink bandwidth. Make sure you do not disable IPSEC pass through. Other than that, the default settings of most consumer NAT routers really should not have any trouble dealing with the Microcell. It's just not that exotic a device.

AT&T has deplorable support for the Microcell. Any outfit that cared even a little would be embarrassed. Don't let them get away with it.
Message 7 of 10

Re: Microcell won't stay up more than a few minutes

So, last night my husband looked at the other thread someone posted about the Westell 7500 modem and changed a bunch of settings based on what they said, passthroughs and things I don't understand, didn't work, so he tried turning off the firewall (which someone did say worked) and that didn't work, so I'm going to try to get a new one sent to me and see how that goes. If all else fails I'm going to tell them to shove their 2 year contract up their you-know-what's cause they made us get a new phone for me to use this device and promised service. Not even happening at this point. I can't make calls anywhere near where I live either because of how many drop zones there are. We are so done with AT&T if I can't get this microcell working.
Message 8 of 10

Re: Microcell won't stay up more than a few minutes

Finally after reaching the last straw my husband called AT&T Friday morning and I went in to the store and switched out the microcell for a new one. The guy there even activated it for me and everything. Got home, plugged it in, it worked! So it was up Friday night, Saturday and Sunday, I think went out one time when our internet was being stupid.


However, today, when I want to talk to him on the phone, the whole point of this stupid thing, it starts going in and out again, although it came back up quickly, still in a 45 minute call, lost it about 3 times. So I reset my modem and microcell, which took a while to come back up and so I had to reset it again, and it came up but still is back to having the blinking 3G light every once and a while. It's not nearly as bad as it was before we returned the other one, at that point it wouldn't stay up at all, but I think I'm going down that road again. Why  would it stay up for 3 days though?


They kept telling me that the line attenuation and upload/download speed dropping below their threshold wouldn't necessarily make it go out, just probably poor voice quality. I checked my speed and it's good, I have no clue what's causing this or if it's our poor line attenuation. Guess I call Centurylink and AT&T today.

Message 9 of 10
Community Support

Re: Microcell won't stay up more than a few minutes

Hello Community members!  Here is some additional information about this type of issue you might find useful.


When a MicroCell will stay up and broadcasting (solid green 3G LED) for a while and then drop off (flashing green LED) at seemingly random intervals, especially if the drop-off happens while calls are in progress over the MicroCell, it generally means that the router/home network is intermittently blocking data traffic from the MicroCell. It is not unusual for router firewalls/security settings to identify the MicroCell as malicious traffic, due to the volume and type of upload/download traffic it uses. This can happen while the MicroCell is being used because the MicroCell is passing more traffic back and forth while a call is in progress than when there is no call in progress.


The following settings should be put into place on the router:

  • DHCP is on
  • Data is not restricted from passing through ports 4500 and 500 (AKA Port Blocking). 
  • MTU size is set to 1492
  • MAC address filtering is either turned off or allowing the MAC address of the AT&T Microcell
  • IPSec Pass-Through is Enabled
  • Block Fragmented Packets is Disabled
  • If using multiple routers, the Microcell must be connected to the first router connected to the broadband modem
  • If the Microcell is connected to a router that is connected to a modem and both the router and the modem have NAT (Network Address Translation) enabled, disable NAT either in the router or the modem.
  • Ensure the modem / router is using the latest software (firmware). Please see the manufacturer's documentation.
  • TCP/UDP Ports
    NOTE:  All ports listed need to be configured for inbound and outbound connections.
    • 123/UDP: NTP timing (NTP traffic)
    • 443/TCP: Https over TLS/SSL for provisioning and management traffic
    • 4500/UDP: IPSec NAT Traversal (for all signaling, data, voice traffic)
    • 500/UDP: IPSec Phase 1 prior to NAT detection (after NAT detection, 4500/UDP is used)
    • 4500/UDP: After NAT detection, 4500/UDP is used

NOTE: Please be advised that the router manufacture or the ISP provider will not provide support for AT&T Microcell, but they can assist with configuring the router settings


If these settings have been put into place on the router and the MicroCell is still experiencing connectivity issues, you can try setting up the MicroCell in the router's DMZ or in DMZPlus mode if either is available on the router. You may need to assign the MicroCell a static IP address first. The MicroCell's MAC address is on a sticker on the bottom of the device, in the same area the EID/serial number is. Any device in the router’s DMZ (or in DMZPlus mode) will be granted an internet connection by the router, but the router will exert no security or firewall controls on its traffic.


If that does not resolve the issue: once the other router settings have been adjusted, and the MicroCell has been replaced, we recommend replacing the router or modem next and/or replacing the router with an alternate make/model if this has not already been done. Which is to say, if the router has been directed to allow the MicroCell’s traffic and/or exert no security control over the MicroCell, but it is still doing so, that would indicate an issue with that router. If this does not resolve the issue or if the customer cannot do this step, please check with your ISP about possible line quality issues or potential blocked ports.

Employee Contributor*
*I am an AT&T employee and the postings on this site are my own and don't necessarily represent AT&T's position, strategies or opinions.
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