This question is a lot more complicated and detailed than the ones I see in your question and answers pieces. I have run this through every other source I can think of, so here goes:
I have a Dell desktop running Vista.
With stunning regularity,when I open iTunes, my library is empty. This sometimes occurs several times a week. Other times, my iTunes library will stay in place for two or three weeks, but rarely longer.
My library is still on my computer. I open my iTunes Media Library and pull everything over - music, movies, podcasts, apps, etc. - and the library is again populated. I have over 17,000 songs in the library, so this procedure takes at least half an hour.
Then, when I go to sync a device, I get a message that this device is synced to another library and all files will be deleted. (We have an iPad2, two iPhone 4s - opposed to 4S - and three iPods). The erase and sync procedure take at least another half hour. When I look at the list of devices associated with my account, it shows two iPods that were retired years ago, before I got the current computer.
I have been on the phone with both Dell and Apple several times. And I have spoken with people at my local Apple Store. I have deleted and re-loaded iTunes a few times. I have looked at numerous on-line forums. I find the occasion reference to this happening to people, but not with the regularity with which it happens to me.
No one has an answer. The best I got was an Apple Store employee who said the Windows version of iTunes wasn't very good.
This issue started when the computer was a little more than one year old. So it worked fine at one time.
Aside from the iTunes issue, my Dell works fine. I am not inclined to buy another computer. I just want to find a solution to this.
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