Level 1: Cadet

MF91 problems resolving DNS / connecting to internet



(apologies in advance for the long post, but I wanted to avoid as much to-and-fro as possible going over basic details/ troubleshooting steps)


We've recently bought a zte mf91 as a prepaid 4G dongle. Some of the time this works great with super-fast speeds, but frequently it reports that it can't connect to the DNS server, and as a result won't provide internet to any devices that connect to it.


This has been tested with a variety of computers and phones (all connect fine to the MF91 wifi) - and when the MF91 is working correctly (giving internet) all of the PCs have been used fine with it.


For example, last night I was trying to connect with a variety of computers and phones (macbook, lenovo notebook, samsung phone) - so it's not a firewall or other problem specific to any of these devices. 




When it's not working, all of these devices connect fine to the MF91 wifi, and can access the device homepage / get what appears to be a valid IP auto-assigned - there appears to be no problem with the hotspot wifi itself.


The hotspot also reports that it's connected to 4G with plenty of signal, and can even access telstra.com fine (interestingly it can't access the crowdsupport forums though - you should consider setting this up as a hard-coded route Smiley Happy


All the rest of the internet appears to be inaccessible due to a failure to contact the DNS server()s hard-coded into the device




- I've tried resetting all the clients & resetting IP addresses / saved network settings on the computers.


- Taken out the battery of the MF91 & left it out for > 1 minute, then started it up again with the same problem



This is pretty bad - the modem's three weeks old and has been working for about four days total - two when we got it, then it stopped for a couple of days, worked again Wed, didn't work till Sunday where it would work in the evening - the rest of the time it appears to be connected as above but isn't actually functional.


My girlfriend's trying to use this for when she's out and about for work but it's actually worse than useless for this case, as it simply won't work a (random) 80% of the time, and you spend 15 minutes trying to see if cconnecting/disconnecting/restarting etc fixes it


This is in glebe, Darling Point & Neutral Bay - all areas where good coverage definitely should be possible, and at times between 9am & 9pm.


Funnily enough we got a telstra dongle because of the advertised reliability, and she ends up having to use her galaxy s3 as a hotspot (on vodafone of all networks!) as it works about ten times more often than the telstra dongle - and she can actually rely on it too.


In any case, does anyone have any ideas for troubleshooting or what can be done to fix this? I haven't tried a hard reset of the modem yet, but the problem appears to be external anyway (and if this is the solution then how often am I going to have to keep on resetting it, and what's going wrong that this needs to be done?) Happy to try any other suggestions people can think of too.


ta - Roger



nb. I've had a search on the forums but the similar threads generally appear to peter out with no resolution:







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Level 1: Cadet

Re: MF91 problems resolving DNS / connecting to internet

Did you manage to reolve this issue?? I am also experiencing this problem.. Bought it and used if for a week or so ( Had it less than 30 days ) - It worked great.. But now I get no DNS to any device I connect to it.. Did a factory reset, left the battery out etc..


I'm thinking it might be data usage related, but I've only used 1GB out of the 5GB alllowance OTB.  I think it stopped working soon after I used 1GB..





Level 1: Cadet

Re: MF91 problems resolving DNS / connecting to internet

Hi there - no I haven't, and have now hit 30 days so the initial data has definitely expired (interestingly, behaviour is unchanged) I think we got to ~1.3gb on the internal usage meter too.

Strangely enough I can't find detail of the included allowance on the ads for this device - I wonder if they changed their mind about either the amount of data or expiry time?

Annoying too, as I'm now putting off buying a recharge. I don't want to throw more money at it without knowing what was actually going wrong (and whether it's only going to work for random intervals).
Community Manager Community Manager
Community Manager

Re: MF91 problems resolving DNS / connecting to internet

Have either of you contacted our mobile faults area on 13 22 00 (say 'mobile faults' at the prompt) for assistance at all?


I would be interested to hear what they were able to do for you.


To check your plan allowance, available balance and status of the account you can chat to us (via the link in my signature) or call the above number but say 'pre-paid' at the prompt.

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Level 4: Private Eye

Re: MF91 problems resolving DNS / connecting to internet

Amazing I went through all of this in a different thread without any good on here?

Level 4: Private Eye
Level 1: Cadet

Re: MF91 problems resolving DNS / connecting to internet

Problem resolved.. Kind of.. I'd blown my data limit - so no DNS.. Not sure why the data consumed doesn't show evenly remotely accurately on the device itself.. But the data usage on the Telstra Usage sitte tells me that my daughter had downloded a few too many movies from ivirus to her ipad...  Smiley Happy





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