Why can I only sync my iPhone on one computer???

Welcome to the discussions,
Select “Manually manage music and videos” to turn off automatic syncing in the Music and Video settings panes. For more info see http://manuals.info.apple.com/enUS/iPhone_UserGuide.pdf , page 72

You did not answer the question - you just posted to a page in the manual that does not answer this question.

There's only one real answer... because that's the way Apple designed it. Anything else is purely someone's opinion. Vent your frustrations here... http://www.apple.com/feedback/iphone.html

Digital Rights Management and Copyright are some of the reasons you can't spread your music on more than one computer using itunes. As already mentioned by paulcb, everything else leads into discussions of Apple policies or procedures or speculation on Apple decisions, which should not be part of the discussions form due to the Apple Discussions Use Agreement, which you also accepted when you signed into this forum. http://discussions.apple.com/help.jspa

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P.S. Being polite is also part of it.

If I am not wrong, the sales terms says that you can have a copy of your downloads on up to 5 devices at any time (which you personally own).

See http://www.apple.com/legal/itunes/au/terms.html#SALE, and read under point 10, usage rule iii. I also believe the rule is equal for most other countries.

So this should really not be an issue if you only have 3-4 devices.

Carl

"If I am not wrong, the sales terms says that you can have a copy of your downloads on up to 5 devices at any time (which you personally own)."

You are wrong. You can authorize up to five COMPUTERS for a specific itunes account.

You can sync as many devices(ipods/iphones) as you like to each of those computers.

I am unsure on how I interpret the rule wrong, but here is a copy of the actual rule which I made a link to in my previous post.

Found under, http://www.apple.com/legal/itunes/au/terms.html#SERVICE, 10. Purchase or Rental of iTunes Content, Usage Rule (iii).
"(iii) Your license of Products as authorised hereunder permits you to use the Products on five iTunes-authorised devices at any time, except in the case of Movie Rentals, as described below."

Also under, http://www.apple.com/legal/itunes/au/terms.html#APPS, 9. USE OF PRODUCTS AND THE SERVICE, Usage rule (iii).
"(iii) You shall be able to store Products on five iTunes-authorized devices at any time."

When I read this, I understand it that the word Products refers to content on iTunes. But it could possibly interpreted differently.

Carl

How you (or anyone in here) interprets those statements is irrelevant. All that is relevant is how Apple interprets them and implements them on their software and devices. If you want to challenge that interpretation, feel free to do so - not here, where it doesn't matter in the least and frankly most of us don't care - take Apple to court. Good luck with that.

Maybe my problem fits in here.

I synced the iPhone to my desktop Mac back home. Now I'm on the road and have downloaded a (free, thirdparty) iPhone app, but can not install it to the phone. And Calendar does not sync either.

It may look like this is a matter of "syncing authorization".
(How) can I move that authorization from my desktop Mac to my MacBook Pro? I did not find an answer to this in the iTunes Help nor in the iPhone manual.

OS 3.1.2 on the iPhone, 10.4.11 on the MacBook, and 10.6.1 on the desktop Mac.

Kind regards - Hening

If you sync to a different computer, all of your music/video/etc will be erased from the iphone and replaced with the music from the new computer.

Maybe my problem fits in here.

I synced the iPhone to my desktop Mac back home. Now I'm on the road and have downloaded a (free, thirdparty) iPhone app, but can not install it to the phone. And Calendar does not sync either.

It may look like this is a matter of "syncing authorization".
(How) can I move that authorization from my desktop Mac to my MacBook Pro? I did not find an answer to this in the iTunes Help nor in the iPhone manual.

OS 3.1.2 on the iPhone, 10.4.11 on the MacBook, and 10.6.1 on the desktop Mac.

Kind regards - Hening

You can just plug in and sync, but you will lose all of your music/video/etc.

Thank you, roamingnome, for your fast reply.

Unfortunately no, I can not plug in and sync. The syncing SEEMS to work; after the progression bar is finished, the text "iPhone sync is complete. OK to disconnect." is displayed. But Calender is not synced, nor is the app showing up on the phone.
(I would not care losing music, because I have none installed - but would "etc" include apps? Anyway, I keep a copy of the app in question in a place outside the Music/iTunes/iTunes Music/Mobile Applications folder.)

iTunes is 9.0.2.

Kind regards - Hening.
Sorry for the duplicate post, that was not intended.

You should be able to sync the app.

Have you tried resetting your iphone?

Yes, and a 2nd time now upon your question.
Could language confusion be the reason? On my computers, the System is in english, but the iPhone is in german. - ?

Kind regards - Hening.