i've been getting this error message too, and it seems to occur when I'm trying to download a TV show that I bought, and while it was downloading, the phone rang, thereby disconnecting my wireless connection. Now, it won't download at all anymore...and this bugs me because my account has been debited and I can't use the file. Is there any way that Apple allows for reimbursement if the file doesn't work/download?
Ok I noticed my quicktime install would not update, so i re-installed it today, and then remembered i also had previously unchecked the qttask entry for quicktime in the start up registry.
once i reinstalled quicktime, and left the registry entry alone my itunes video download finished without 0xFFFE7958 error the FINALLY =) !!!
Having the same problem as many others here. I keep getting error message "0xFFFE7958". I have tried about 25 times over several days with 2 different computers using both tiger and panther and I still cant get the file to download. The episode that is giving me trouble is "Orientation" in second season of Lost. I have noticed that other peeps have had trouble with the same file. I don't think it's me!! I won't be downloading any itunes content until this gets fixed.
I was getting this same error. I had also been having lots of problems with corrupted downloads in general.
If you have NVidia nForce 4 chipset, try downloading the latest system drivers from the NVidia web site. Doing so solved all of my download problems including my ITunes video downloads.