Unable to sync with Exchange server over GPRS from MDA Pro.

[Dazbot]

As subject says, I cannot get it to work over GPRS, but using WiFi works fine.

It gets a far as saying Emai 0/8 and then just displays Synchroniszed Today: 10:51. (which is about 30mins ago when I used Wifi to sync) The icon is yellow and next to it I've got Attention required, clicking that I get.

I can use Internet Explorer fine over GPRS as well with no problems.

Results:
Synchronization could not be completed. Try again later. Support code 0x8503001A (The response was compressed but had an invalid gzip header.)

I can sync with another email server fine. I cannot sync with other email accounts on the same server. The server is an Win 2003 SBS SP1 with Exchange SP2

Thanks

[Janak Parekh]

As subject says, I cannot get it to work over GPRS, but using WiFi works fine.
Is your WiFi connection on the LAN with the Exchange Server, or remote? It sounds like somehow the IIS setup differentiates between LAN and Internet connections.

Alternatively, your ISP might be forcing you to go through a HTTP proxy for all traffic to reduce GPRS consumption. Are you set up to use SSL with Exchange ActiveSync? Generally, SSL traffic is not proxied. Exchange ActiveSync uses SSL by default, but some people turn it off to work around the certificate signing problem.

--janak

[Dazbot]

As subject says, I cannot get it to work over GPRS, but using WiFi works fine.
Is your WiFi connection on the LAN with the Exchange Server, or remote? It sounds like somehow the IIS setup differentiates between LAN and Internet connections.

Alternatively, your ISP might be forcing you to go through a HTTP proxy for all traffic to reduce GPRS consumption. Are you set up to use SSL with Exchange ActiveSync? Generally, SSL traffic is not proxied. Exchange ActiveSync uses SSL by default, but some people turn it off to work around the certificate signing problem.

--janak

Thanks for replying,

No the WiFi and Exchange server are at different locations.

I not using SSL but I have managed to sync with a normal Exchange server that is also remote, that's running Windows 2003 Enterprise and Exchange 2003 SP2 Enterprise.

I haven't try activesync through GPRS on T-mobile before, maybe that is causing the issue, I have already spoken to T-mobile who tell me its the server as I can access websites via GPRS. I would of tried my company vodaphone sim but the phone is locked to T-mobile.

Does Small Business Server 2003 make a difference (my boss seems to think it does), I have since tried it on our own SBS Exchange SP2 server and had the same problem (it only works over WiFi)

I no longer have the MDA Pro to test anything with, the owner is going abroad and said I can have it back in 2 weeks to fix. Neither do I have another WM5 Phone Editon or any Phone Edition to try it on. All I have is my h2210 and Nokia 6230i with a Vodaphone sim that works fine.

[Janak Parekh]

I not using SSL but I have managed to sync with a normal Exchange server that is also remote, that's running Windows 2003 Enterprise and Exchange 2003 SP2 Enterprise.
I would encourage you to use SSL from a security standpoint. You can use self-signed certificates with modern Pocket PCs if you are willing to invest the time into learning how to work with the Certificate Authority application (if you don't know it already).

I haven't try activesync through GPRS on T-mobile before, maybe that is causing the issue, I have already spoken to T-mobile who tell me its the server as I can access websites via GPRS. I would of tried my company vodaphone sim but the phone is locked to T-mobile.
I believe T-Mobile USA does use a proxy server for non-SSL HTTP traffic (I believe EAS is over HTTP) -- this compresses the data and reduces transit time -- and that could easily mess with Exchange Activesync. However, any such proxy server wouldn't (couldn't) proxy SSL.

BTW, this doesn't quite dovetail with your previous comment. Are you saying you've sync'ed against one Exchange Server but are unsuccessful with the other, both over T-Mobile GPRS and both non-SSL?

Does Small Business Server 2003 make a difference (my boss seems to think it does), I have since tried it on our own SBS Exchange SP2 server and had the same problem (it only works over WiFi)
Possible -- I don't use Small Business Server. I got burned years ago with SBS 4.5 and its onerous domain controller requirements, and I've since sworn it off.

All I have is my h2210 and Nokia 6230i with a Vodaphone sim that works fine.
Too many variables to say for sure. ;) BTW, the above is a first-cut guess. It's entirely possible I'm wrong and something else is the cause, but if it works over WiFi, I'm not sure what else about the GPRS connection could be messing up the process.

--janak

[Dazbot]

I not using SSL but I have managed to sync with a normal Exchange server that is also remote, that's running Windows 2003 Enterprise and Exchange 2003 SP2 Enterprise.
I would encourage you to use SSL from a security standpoint. You can use self-signed certificates with modern Pocket PCs if you are willing to invest the time into learning how to work with the Certificate Authority application (if you don't know it already).

I will try using SSL when I get it back, I wasn't sure how to go about it.

I haven't try activesync through GPRS on T-mobile before, maybe that is causing the issue, I have already spoken to T-mobile who tell me its the server as I can access websites via GPRS. I would of tried my company vodaphone sim but the phone is locked to T-mobile.
I believe T-Mobile USA does use a proxy server for non-SSL HTTP traffic (I believe EAS is over HTTP) -- this compresses the data and reduces transit time -- and that could easily mess with Exchange Activesync. However, any such proxy server wouldn't (couldn't) proxy SSL.

BTW, this doesn't quite dovetail with your previous comment. Are you saying you've sync'ed against one Exchange Server but are unsuccessful with the other, both over T-Mobile GPRS and both non-SSL?

Yes that is correct, 2 SBS servers failed (one of which I sync with using a Nokia and Vodaphone) but one Win 2003 Enterprise Server with Exchange 2003 server worked fine.

Does Small Business Server 2003 make a difference (my boss seems to think it does), I have since tried it on our own SBS Exchange SP2 server and had the same problem (it only works over WiFi)
Possible -- I don't use Small Business Server. I got burned years ago with SBS 4.5 and its onerous domain controller requirements, and I've since sworn it off.

Your not the only one, installation drives me up the wall, especially as we build them at work where we use a different IP subnet, it also moans about our SBS servers DHCP. Sophos SBE doesn't like changing subnets either it has to be installed once onsite or else it can't communicate with clients properly.

All I have is my h2210 and Nokia 6230i with a Vodaphone sim that works fine.
Too many variables to say for sure. ;) BTW, the above is a first-cut guess. It's entirely possible I'm wrong and something else is the cause, but if it works over WiFi, I'm not sure what else about the GPRS connection could be messing up the process.

--janak

I could just do with a K-Jam or Jasjar that isn't locked to test this out with on different networks.

[Janak Parekh]

I will try using SSL when I get it back, I wasn't sure how to go about it.
If I remember correctly, you have to set it up for the IIS server. It's a bit of a pain -- you need to generate a Certificate Signing Request, sign it using Certificate Authority, and then import the certificate back into IIS. Finally, you need to export the certificate (either the host's or the CA's) copy it onto the device, and tap on it in File Explorer to import it so it's trusted.

Yes that is correct, 2 SBS servers failed (one of which I sync with using a Nokia and Vodaphone) but one Win 2003 Enterprise Server with Exchange 2003 server worked fine.
Huh. If the Win2003 Enterprise setup worked fine over T-Mobile, and is non-SSL, then my theory goes out the window. :(

I could just do with a K-Jam or Jasjar that isn't locked to test this out with on different networks.
That would be ideal if you can get your hands on one. :)

--janak

[Dazbot]

I will try using SSL when I get it back, I wasn't sure how to go about it.
If I remember correctly, you have to set it up for the IIS server. It's a bit of a pain -- you need to generate a Certificate Signing Request, sign it using Certificate Authority, and then import the certificate back into IIS. Finally, you need to export the certificate (either the host's or the CA's) copy it onto the device, and tap on it in File Explorer to import it so it's trusted.

OK, I'll give it a go.

Yes that is correct, 2 SBS servers failed (one of which I sync with using a Nokia and Vodaphone) but one Win 2003 Enterprise Server with Exchange 2003 server worked fine.
Huh. If the Win2003 Enterprise setup worked fine over T-Mobile, and is non-SSL, then my theory goes out the window. :(

It's still worth a go, I only tried it once with the Win2003 Enterprise server, maybe it was a one off.

[Dazbot]

Well I got it running using SSL, T-Mobile told me that they do have a proxy server running and that they don't support 3rd party applications like exchange activesync on the phone.

They also kept trying to shift the blame to a problem with the SBS 2003 server. (standard answer I suppose)

I still have a PAYG sim with T-Mobile which has GPRS on it, they charge £20 per MEGABYTE to use the service 8O. </moan about t-mobile>