Consider this a public service announcement for MSPs administrating a fleet of Apple iPhone’s and a Microsoft Exchange Online deployment: any device running iOS 4.0 needs a patch to continue using ActiveSync. Here are the details.

Microsoft put out the alert in a blog entry dated July 6 (2010), offering a link to Apple’s own site to download the configuration patch necessary to fix the problem. If users don’t install this patch, the blog says, the offending Apple iOS 4.0-running device — which can be an iPhone 3G, iPhone 3GS, an iPhone 4, or even an iPod touch — can result in “degraded performance,” including an out-and-out inability to use ActiveSync with Exchange Online.

In the comments to the original blog post, someone left a link to a patch installation pictorial walk-through. It’s in German originally, but running it through the automatic Microsoft Translate gives up a fairly easy-to-follow guide.

As the iPhone gets more respect as an enterprise device, issues like this are going to keep coming up. Fortunately for all involved, the market’s starting to come around with tools to help with exactly this.

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