The company behind those floating ads that dance across Web pages has developed a way to restore the data profiles that many privacy-conscious users try to delete from their computers.
Most users don't know what they are doing when they run antispyware programs that delete the profiles, known as cookies, said Mookie Tenembaum, founder of United Virtualities Inc.
By deleting cookies, he said, users thwart efforts by Web sites to prevent the same ads from appearing over and over. Tenembaum said visitors are also forced to repeatedly enter usernames and passwords, which are sometimes stored in the profiles.
United Virtualities calls the product Persistent Identification Element. It taps a separate profile system that's found in Macromedia Inc.'s Flash and that's not generally affected by antispyware programs.
Using the product, when a Web site discovers a cookie missing, it can look for a backup in Flash and restore the cookie.
Richard M. Smith, a privacy and security consultant in Cambridge, Mass., was critical of United Virtualities.
"Companies should respect people's choices," he said, "If a consumer makes the effort of getting antispyware software, they don't want this stuff."