Thursday night I decided to go ahead and install the latest iTunes version 9.1 (the iPad compatibility update), even though I usually wait a little while after an update comes out just in case there are any bugs that surface. After installing the update my computer would no longer recognize my iPhone. Each time I connected the phone I would get a message stating that SyncServer had stopped. SyncServer is the process that allows the synchronization of the iTouch an iPhone devices not only with the iTunes library, but also with the MobileMe service.
I figured something must have gone wrong with the installation or with the conversion of the iTunes library to the new library format, so I removed and reinstalled iTunes. Well, that didn’t do the trick; I still had the same SyncServer error. A quick Google search didn’t yield anything useful that might indicate a solution to the problem, so in a panic I contacted a friend who works for Apple for assistance. We went through the usual iTunes support routines to resolve errors and after an hour and a half still could not resolve the error.
Being a software developer myself, I proposed that we look at the offending program that was being called by SyncServer rather than suspect it was SyncServer itself causing the problem. libtidy.dll!__tidyAttrNext@4 was the indicated program/entry point that seemed to be causing the problem. A command prompt search of the hard drive found that there were indeed conflicts with this DLL. There were two versions of this DLL on the computer, one for Apple and another for one of my development environments. Renaming the libtidy.dll from the development software and restarting iTunes did the trick. The new version of iTunes works like a champ.
Apparently version 9.1 installs a newer libtidy.dll that probably has a modified AttrNext routine.
If you experience this same problem but find that you don’t have another libtidy.dll on your system, try looking for duplicate copies of sqlite3.dll or libxml2.dll.
Update: My reference to sqlit3.dll should have been sqlite3.dll (thanks Umurkan!)
Update: I found that Binary Fortress has a fix for this: http://www.binaryfortress.com/itunes-com-fix/ . I have not tested this but I think it is worth a try if you are still having problems with iTunes.
Update: For iTunes backup problems, see this post: https://cgatesmobile.wordpress.com/2010/07/04/itunes-and-your-time-zone/