Apple discreetly launched iTunes 12.6.3, an older version of iTunes for Mac and PC users, that enables users to download applications. The Apple logo is pictured inside the newly opened Omotesando Apple store at a shopping district in Tokyo June 26, 2014. REUTERS/Yuya Shino/File Photo Reddit users captured how Apple secretly brought back the iTunes desktop. Apple pulled access to the App Store in iTunes for its standard version in September 2017 with the release of 12.7 but continued to offer a dedicated version of iTunes for those who needed this level of functionality, stamped as version 12.6.3 on its initial release. In terms of being able to access this particular version, Apple has quietly made download links for iTunes 12.6.4.3.
I have iTunes 12.6.3.6 on High Sierra (10.13.6). For roughly a week, iTunes has failed to download iOS app updates, or new purchases from the store. It can see the store, and can see that updates are available (the list keeps growing), but updating fails. iTunes says, 'Downloading...', and then quickly stops. There is no error message.
The same thing happens when I try to download a new app from the store w/in iTunes.
I tried updating iTunes to 12.6.5, but installation failed because it's too old, even when I ignore the certificate error.
I've tried a few usual things like restarting and trashing preferences, but nothing terribly drastic yet. I've seen a couple other people with this problem around the internet, but no one's offered a solution.