When it was unveiled, BlackBerry 10 was seen as the shining light for RIM BlackBerry as it heads back to the path of profitability. The platform’s fans think this is the one that will succeed, but the company still has a major problem ahead of it. It’s traditionally strong enterprise customer base is shrinking.

Tom’s Hardware reports that Home Depot is taking its employees off BlackBerry in favor of Apple’s iPhone. It’s a pretty hard hit for the company as Home Depot had 10,000 employees on the BlackBerry platform. It’s unknown if the transition to the iPhone occurred before or after the BlackBerry 10 announcement.

This isn’t the first major loss for BlackBerry as other major businesses and government agencies have been moving their employees off BlackBerry in favor of iOS or Android devices. Late last year, Yahoo kickstarted the migration away from BlackBerry when the company offered to buy every employee a smartphone, but only offered iPhones or Android devices. Soon after, government consulting firm Booz Allen and the U.S. National Transportation Safety Board also moved their employees off of BlackBerry.

Despite all of this bad news, BlackBerry 10 may be doing decently well. BlackBerry announced last week that first day sales of the Z10 was the best the company had ever seen. In a statement to Tom’s Hardware, the company also said that “over 2,7000 unique businesses in North America already registered for our BlackBerry 10 Ready Program.”

In short, BlackBerry is losing business, and that’s a bad thing. To counter this, it’s Z10 handsets seem to be doing decently well, and it still has quite a few Enterprise customers. That’s a good thing. We’ll have to wait a bit longer to see if the good outweighs the bad when BlackBerry 10 launches across all major carriers in the U.S. next month.