TaxCycle automatically adds file extensions to Windows as new modules appear. If for some reason it does not do this, you can do it manually from two locations.
Associate File Extensions From Options
From the Start screen, click Options in the blue bar on the left side. If you have a file open, go to the File menu, then click Options.
On the left, expand Files and folders, then click on File Settings.
Click the button to Associate TaxCycle files with Windows®.
Register File Extensions From the Help Screen
Go to the Start screen.
Click Help.
Click Modules & Extensions.
Click the Register file extensions link.
The following message will display: Associate TaxCycle file extensions with Windows®: this requires administrative privileges. Click the Associate button.
Windows® will ask Do you want to allow the following program to make changes to this computer?.