Hi all and thanks in advance. First, my knowledge of Exchange is limited...we had it installed for us a few years ago for our email and (for what we do) have not had many issues with it.  For one person in our company, there is a calendar setup for him. It was setup via a browser and going to http://exchangeserverip/exchange and logging in to his account. I also had his secretary accessing his calendar. Both were are able to view, update, delete, etc. The only way they connect to the calender is: she uses an iPad and he uses and iPad and a Blackberry. This has been working fine for a few years. A few weeks ago, she called me and said everything prior to 3 months ago was gone. I looked at the calendar in the only way I knew how (which was from the browser) and saw she was correct, it was all missing. I also verified it on the Managers two devices that it was all missing. No changes have been made to the iPads and nothing (as far as I know) was changed on the Blackberry. Neither one uses any version of Outlook for email (we are primarily a Thunderbird office). Any ideas as to why there is only 3 months of scheduling available now? And, more importantly, is there any chance that the missing years are still in Exchange somewhere and just not showing? Thank you again in advance.

Software/Hardware used:
Exchange 2003 iPad Blackberry