Hello, we have SBS 2008.
About three months ago the Dr's Iphone stopped syncing calendar items and the server got extremely slow. I re-loaded the server and applied all updates and Exchange service packs. Everything works great. However when his phone is set to sync everything gets extremely slow, store.exe uses about 27+ percent of the CPU and his calendar still does not sync to the phone. He has a large amount of recurring and appointments in general. On the iphone we have installed the newest 4.0.1 OS and also tried this patch
So I am out of ideas. Apple is out of ideas and says its Exchange. Exchange troublehshooting tools report an extremely high RPC load from his phone. When it tries to sync.