Hi
I have a exchange 2010 and I got a Nokia Lumia 800 (a gift from a contest) 
.
I got these error to try to configure the Nokia Lumia 800..
“Error Code 80072F0D”
Solution:
1. Open the OWA into a IE browser but don't log in. (I used IE 8)
2. right-click the webpage and select 'Properties'
3. on the 'General' Tab click the 'Certificates' button on the bottom.
4. select the 'Details' tab
5. click the 'Copy to File' button
6. this opens the Exporter Wizard; click 'Next'
7. I exported the certificate into each available format and named each file with a different number suffix. I chose to export to my desktop. For me there were 3 formats available two .cer and one .p7b.
8. For the .p7b select the "include all certificates" option
9. Copy and paste the .p7b file. Rename the newly copied file by changing the .p7b extension to .cer. This is b/c another post noted that changning the .p7b extension to .cer worked. I didn't take chances so I did both.
10. Email all of the files to yourself. I used desktop outlook to hotmail as hotmail is already synced on my phone.
11. Goto phone, open the email and tap the first attached file. Tap again after it has downloaded in the message and you should get a successful install window. Press ok or whatever the equivalent option is on this window to return to email.
12. repeat for the remaining files.
13. I noticed for the .p7b file and the file with the renamed .cer extension, the phone downloader provided additional information about the certificate. I think the .p7b file is the certificate you are after but I didn't take chances and did all of them as I didn't want to redo the steps again. These files are only 1kb anyways.
14. delete outlook account that failed to sync if you haven't already done so.
15. turn the phone off (power cycle/soft reset, etc).
16. turn phone back on.
17. threaten phone if the following does not work.
18. Add Outlook account via Settings.
19. Add in your log-in and server information. ENSURE that your domain and server information is correct. The generic MS steps that state the information before the @ in your email is your user name is not always correct. Whatever you use to login to OWA is what you should enter here.
20. Phone should sync.
Regards
