Quarterdeck Corp, Marina Del Rey has acqured Vertisoft Systems Inc, developer and publisher of utility software and a leading direct mail marketer, for 3.5m new Quarterdeck shares, valuing the target at an indicated $26.7m. Annualized sales at Vertisoft are running at about $16m. Products include Fix-It, a troubleshooting utility to find software conflicts and hardware configuration errors in Windows95 systems and fix them with a click of a button. Remove-It is an application removal utility; Vertisoft Zip-It is a Windows file compression utility; and Name-it is a seamless method to use long file names in Windows 3.X applications run under Windows95.