"Sure, it may not be this massive amount of data, but these are things that you'll never use," Fowler said. "You'll probably never activate Chinese."
Fowler pointed out that there is a pop-up window with more information on one of the warning screens. That message justified the warnings and said MacKeeper found "a relatively large amount of unneeded files" that could eventually affect a computer's performance or security.
MacKeeper has also taken heat for aggressive and pervasive advertising. Fowler said the company buys upwards of 60 million ad impressions a month, making it one of the largest buyers of web traffic aimed at Mac users. MacKeeper has even posted a statement on its website to answer why people see its ads so often.
It has also had issues with some affiliate advertisers, who were attracted by the 50 percent commissions Kromtech pays for sales of MacKeeper.
Some affiliates have wrapped MacKeeper ads into advertising software programs, or adware. It's a category of much-loathed tools that offer some functionality such as search but are primarily designed to deliver ads.
Thomas Reed, who writes The Safe Mac blog, discovered the reach of MacKeeper affiliates. Reed developed a program called AdwareMedic, which removes adware from Macs. The program is free. Reed wrote in November that he found an adware program called Downlite that, if installed on a Mac, would redirect someone to MacKeeper's website site if they tried to download AdwareMedic.
Kromtech has taken steps to reign in unethical affiliates, Fowler said. More than 80 percent of ZeoBIT's affiliate agreements have since been suspended, and the company's new compliance department closely vets new ones.
Still, the bad practices of former affiliates caused damage to MacKeeper's reputation, Fowler said.
These days, MacKeeper has gone to a subscription-based pricing model rather than a $39.95 one-off payment. It costs $7.95 a month in the U.S. for the premium, year-long plan. Its latest feature is offering phone support from Apple-certified technicians, which it calls Human Inside.
On its website, MacKeeper assigns a value to each of its tools, contending the bundle would be worth $510 if bought individually.
"Save up to 97 percent," it says.
But many of the tools in the software bundle, which includes an antivirus scanner and 15 other utilities, are already in OS X or available for free.
For example, MacKeeper licenses technology in its AV scanner from Germany-based Avira, which offers its Mac security product for free. On its pricing page, MacKeeper estimates the value of an AV scanner at $79.
Curiously, MacKeeper doesn't offer updates or what's called real-time protection — where files that are downloaded or opened are scanned for malware — unless the customer buys its "premium" version, according to Dennis Technology Labs, which also tested MacKeeper for IDG News Service.
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