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  Outlook iCloud Synchronization by iCal4OL (via CalDAV)

FAQ English

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This is a guide for proper configuration of iCal4OL to synchronize Outlook with the iCloud/CalDAV:

This guide is certainly useful for other CalDAV servers such EGroupware, DAViCal, SOGo, OwnlCloud, .., too.

First of all, download the demo from the download page (or customer page) and install it.

There is also a version which can be installed without administrator rights (there is also a such full version).
Demo runs for 14 days. Prerequisites see here!
Then start iCal4OL..

The demo shows an entry screen, which is the only difference from the full version.
Click on the button [Start Program]..
Possible issues to this point see FAQ.

If you DO NOT intend to sync Exchange Public Folders or folders in different integrated *.PST files, do not mark on the tab "Options - Exchange/*.pst" the option:
[ ] Scan for Exchange Public Folders and in additional *.PST files, too
Please read about Exchange Support here in der FAQ.
For a large Exchange structure the first startup may take up to 15 minutes. All Outlook folders are scanned, which can be synchronized (calendar, tasks and contacts).

In the forum you will find additional topics about iCloud, e.g:

  • iCloud - Outlook Sync by iCal4OL (from the "early days"..)
  • Outlook 2003 Kalender vollständig nach iCloud übertragen GERMAN
  • iCloud-Sync und Aufgaben GERMAN
  • ..

    iCal4OL offers many options to synchronize exactly as you wish.
    First you should run the Assistant [Other] on tab "Who" for initial CalDAV Setup.

    Most CalDAV web solutions are not returning the fullname and email address (iCloud does).
    You must configure the fields on tab "Who" manually, after using the assistant:

  • Fullname (as on server): use the fullname field of your Outlook default email address (if different)
  • E-Mail (as on server): you must enter your email address as on server

    (Those two fields are used to map attendee info to your Outlook identity..)
  • Your timezone: This field can't be empty. Do NOT modifiy the selected timezone rule

    The assistant looks like this.. Enter her the URL, AppleID (lowercase!) and Password.
    With active two-factor authentification you must first generate an app password, see here!

    For other CalDAV solutions enter the URL of a server calendar collection (or the principal address). See the browser interface of your solution.
    In addition, you can configure here already some basic options.

    Retrieve the confiugration and save it.. If this is not working, there is a network issue. There are unfortunately many possibilities for this..
    iCal4OL is actually in the sandwich of Outlook, OS and iCloud!

    1. Did you enter your AppleID in lowercase?
    2. A firewall (of OS or of an antivirus security package) might be active. You must allow iCal4OL to connect to the internet.
    3. A proxy may be active. If a proxy is configured in Internet Explorer under Internet Options, add those settings on tab "Options- Proxy". But *.PAC configuration files (JavaScript) are not supported by iCal4OL. Download and analyze *.pac file in a browser and identify the actual proxy in it. Enter the proxy on tab "Options-Proxy" manually, save Default.ini and restart the assistant.
    4. iCal4OL is using LibCurl.dll as default for HTTP(S).
      iCal4OL has two other HTTP_DLL's integrated, which can be activated on tab "Options - HTTP_DLL".
      WinInet.dll does use a lot of CPU, does not support NTLM authorisation for proxy, but does intherit the proxy settings of IE (Internet Options) except for *.pac file.
      WinHttp.dll can't be used for CalDAV-Scheduling (Flag inbox), because of a bug! Therefore you should not use it for iCloud, Darwin, DAViCal, SOGo.
      LibCurl.dll ist normally the best choice. You will need to configure a proxy for it on tab "Options - Proxy".
      - Deactivate [X] Debug for production.
      - From 2.15.0 LibCurl (7.40) does not support anymore unsecure SSLv3 (SSL23_GET_SERVER_HELLO:unsupported protocol).
    5. For iCloud the flag no_auth is default (even if not visible).
      With this flag, a BASIC REALM Header (=Server Authentification) will be embedded by iCal4OL directly. This way the Authentication Negotiation will not be done by the HTTP-DLL's. Most servers are supporting BASIC REALM, but not all. It will reduce the http traffic..
    If the Assistant is working, there are maybe some additional questions you'll have to answer:
  • whether additional own calendar should be synced..
  • whether additional delegated calendar (proxy-read/write) should be synced..
  • but you are not asked about additional reminders (tasks collections)! See here how to re-configure it later.

    If multiple calendars syncs must be configured by the assistant, multiple configuration files (*.ini) will be created automatically. You will see those later on tab "Run" chained together, because only one Calendar Sync can be configured per .ini file.

    Click on [New] to add an Outlook subcalendar. Drag&Drop of URI's is possible (exchange server colletion URI's). Green => will get synced!

    More about multiple *.ini configurations see FAQ.

    Before you start the first sync - Optimization:

  • iCal4OL stores for new installations (>=2.12.15) the Sync Fields not anymore as userdefinded MAPI fields (e.g. in Outlook.pst).
    This was not optimal for Exchange environments (the printout in memostyle will show those fields, even for attendees)!
    Older installations of iCal4OL can be re-configured, to use an external DB for the Sync Fields (see screenshot below).
    In this screenshot, the folders are "monitored" for deleted items. Actually, it's not recommended to use it, due to a rare Outlook issues (not re-finding items).
    Without those options, only the "Deleted Items" Folder of Outlook is used for detection of deleted items, which in most scenarios is sufficient!
    See also this FAQ article!

  • I generally advice NOT to upload Birthday and Anniversary Events (of Contacts).
    The reason here is the (unbearable) behavior of some Outlook installations: a Contact Change often produces as a duplicated birthday event!
    This can be prevented by an export filter: /(Birthda.*|Annivers.*)/ or /([A-Z,a-z,\ ]*\'[s]\ Birthday)/,
    or in German Outlook: /(^Geburtsta.*|^Jahresta.*)/
    (On tab "Maintenance" it is possible to get rid of duplicates.)

    Importfilter is on tab "1.1 More" (activate enhanced options on tab "1. How"):

  • Since July 2016, iCloud does always send email invitation to attendees again (you sent them already by Outlook).
    Apple is now ignoring the CalDAV-Scheduling spec "SCHEDULE-AGENT=CLIENT". This was just addressed in 2.16.4 for only new meetings, see here.
    Note: The default setting of iCal4OL by the assistants on tab "Who" are optimal!
    In general, if you never uploaded meetings before (new installation), you could use special flags in field "UserID:" on tab "1. How" to prevent uploading attendee information: no_att bodyatt (No_Attendees BodyAttendees)
    Because every solution works differently, here some hints: For OwnCloud+Baikal+Fruux there is no issue uploading (or not) attendees infos. Whereas SOGo+eGroupware are depending on attendee infos (to show those events in attendee calendars). If unclear, please ask..

  • In Outlook generated Public Holidays may cause sync issues!
    If this Outlook option was active, you should change before first sync on tab "1. How", the selected time period rule to -31 to +365, or perhaps better, activate the enhanced options (1.How) and on tab "2.1 More - Export" enter the category filter -Holiday", to exclude them for upload. Reasons:
    - Those events may be defective, resulting in sync issues (ScanPST.exe may help).
    - Syncs are slow, because iCal4OL downloads only 3 years into the future. Additional events have to be tested one by one, if already on the CalDAV server.

  • iCloud, newer Darwin CalendarServer, SOGo and DAViCal are supporting the modern WebDAV REPORT sync-collection, which normally a little bit faster than a normal sync.
    But for security reason, this is not activated by default. If you want to try it, replace the flag multiget with the flag sync.

  • Last but not least - some info about the flag getctag. Sadly, this can't work with iCloud, because Apple does not follow the iCalendar Specs for LAST-MODIFIED!
    And out there in the world is a CalDAV App, which may change a HREF of an element (HREF is like a file name for an event).
    Therefore iCal4OL will not test on the Collection Tag, if something or nothing has changed on the server. Using this flag, will skip unnessary download sync tests in iCal4OL, and only check new modified events during upload (last saved HREF and ETAG will be used).

    The Contact Sync must be (re-)configured manually!

    Important: under CONTROL PANEL - Phone and Modem Options - Location .. enter the correct area code, or even better use "International Freephone Service"!
    Otherwise the plus sign in front of a phone number may be ommitted during download sync = Outlook Issue; e.g. +41 893..

    You'll find the "CardDAV Contact Synchronization" on tab "Contacts". You may want to start this first separately here (or test it with "[X] Simulation" for analysing the LOG.txt). Read the tooltips of the options, too!

    Now, the first interactive Sync is due. Go on tab "Run" and save the configuration (Default.ini).

    After the sync look into LOG.txt. If there was an error during the sync, it will be written into the LOG.txt and the backcolor of the counter frame (read,skipped..) is red.
    If you need support, you must first go on tab "1. How" and add in addition(!) the flag debug into the field "UserID:", then run the sync again. Email this LOG.txt to get support, if something went wrong!

  • The detailed CalDAV Documentation with explanation of all flags, you'll find in the forum!

    In order to sync automatically in the background, for example when you logon to your machine, some additional settings are proposed to activate on tab "Options - Startup":

    Now look under START - All Programs - iCal4OL .. Many shortcuts (links) are available to start iCal4OL, e.g. directly in background.
    All background syns possibilities are explained here.

    In Windows 8, the Start Menu is not docked anymore. Therefore enter in the address field of an explorer window:
    Version with admin rights: C:\ProgramData\Microsoft\Windows\Start Menu\iCal4OL\
    Version without admin rights: %APPDATA%\Microsoft\Windows\Start Menu\iCal4OL\

    Perhaps you first want to fine tune on tab "Options - Startup (General)", if Outlook should be opened together with iCal4OL, and if syncs should pause (or end) when Outlook gets closed.

    You may want to copy such a link to your STARTUP (AUTOSTART) Folder or on DESKTOP (Drag&Drop with right mouse button and choose "Copy" or "Make a link"):

    That's it! Please read the FAQ, too. Everything is explained somewhere (and some details are in the forum).

  • MS-Outlook® ist eingetragenes Warenzeichen der Microsoft Corp.,   iCloud® ist eingetragenes Warenzeichen der Apple Inc.
    iCal4OL © ical4ol [at]