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I have been struggling with persistent errors with Outlook for Mac for months and I am just fed up with it. After having re-archived all my mail and re-built my local Outlook calendar (cleared the cache and downloaded last data from Exchange server) yesterday, I am still being plagued with error messages. Examples as follows:
Error code 17886. Error: An unknown error has occurred in Outlook. Details: Mail could not be sent.
Error code 18000. Error: While downloading the meeting It's Breakfast Time!, some attachments may have been lost. Details: To try to recover the attachments, hold down CONTROL, click the calendar in the Navigation Pane, and then click Folder Properties. Then empty the cache. Outlook will then download the latest version of the meeting to your calendar. Open the event again. (This is precisely what I did yesterday and it took 10+ hours for everything to sync!)
Error code 19995. Error: Permission Error. The folder "" could not be moved or deleted because you do not have the appropriate permission on the server. Details [none]
Error code 19707. Error: Could not synchronize record: Work From Home today to Exchange server: Esecuritel. Details: The request timed out.
If anyone can provide any input to the root cause here - local Outlook installation or Exchange server; or can provide specific help on one of the examples provided that would be fantastic.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Answer accepted by question author
Mac uses EWA where PCs use a different setting. It could be something on your server that needs to be set.
Since we are consumer-end forums, this issue would be better suited for the Exchange forums:
http://social.technet.microsoft.com/Forums/en-US/exchangesvrclients/threads
Outlook 14.3.7
I started having this problem about three months ago, with "Could not synchronize record" errors and Error code -19707. I have tried rebuilding the local Main Identity database, and then twice removing it entirely and setting up from scratch.
The behavior is alway the same: I get the latest messages downloaded when Outlook account is setup, but then no more mail gets downloaded. Outlook just sits with "Inbox: Downloading" in the bottom status bar, but no more new mail ever arrives.
I have been using Apple Mail connected to Exchange, and OWA, for the last three months, both of which work without a problem.
Having paid for the Outlook software it is very frustrating to have it be effectively useless, and having spent several hours attempting to get it to work.
It would be good to see Microsoft take these critical problems seriously.
Having the same error (-17886) and failure to send from Mac running current version of Outlook 2011. User's mail works fine using OWA, iOS, and PC, but when using Outlook for Mac, gets error constantly, sometimes has to send an email 7 or more times to get it to go out.
Have removed and recreated profile more than once, reinstalled Office, rebuilt entire machine, tested on multiple Macs using different builds of Mac OS (10.7 and 10.8) and Office, same result every time. Problem came on about 5 months ago, no change in hardware or software that should have triggered onset.
Any thoughts? Seems to point to something on the Exchange side since it spans every Mac we use. Thanks for your help.
You should never rebuild an Identity with an Exchange account. If you have mail under "On My Computer" folders and Outlook will not open you might be forced to rebuild, but you should immediately delete the Exchange account and then add it back to let the messages download from the server. If you damage the Exchange data and it uploads back to the server it's difficult to clean up.
I suggest you move to a new Identity. How to move your data to a new Identity
Exchange Basics
The Inbox syncs more frequently than any other and should be kept as clean as possible. (this is the number one cause of problems with sync). Do NOT make subfolders under the Inbox.
Any folder with more than a few thousand messages is going to take some time to fully come down when you first sync your account. Due to the design of Outlook's sync engine (and how exchange works), you will see the 512 newest messages in a folder at the initial start of sync then the rest of the folder's contents will be back filled before you see any mail that arrives after this point. This is why it will look like you are not getting new mail when a folder is still going through initial sync. This is also further exacerbated by an Exchange issue where it gets unnecessary change events before the newer mail arrives. If you carefully watch the progress during the sync of a folder with greater than a couple thousand messages, you will see "Updating local..." a lot before the newer mail starts arriving (newer than the initial 512 that come down).
Outlook checks the server for updates every minute, any folder that has updates will subsequently be synced. Since Outlook has a limit on how many folders can be synced at a time, there can be a queue of folders waiting. The Inbox does get high priority so it will generally sync before other folders that also need to sync.
MORE INFO
Recommended Mailbox Size Limits
While you can stuff a folder with thousands of messages, you should keep folders under 2GB. Outlook uses the 2GB .mbox.
