When one field of a CICS screen is changed to use extended color, all fields on the screen are affected when using IBM Personal Communications.
Displaying the host screen in which all fields are constituted with basic attribute only, the fields are displayed by 4 colors that are defined as "basic color" in color mapping panel.
If the host screen design is modified to add 'yellow' attribute on a field, colors on the rest of fields in the same screen are changed to 'default' colors of 'extended color' on color mapping. The "default" extended colors are white and green.
Resolving the problem
If extended color attribute is added to part of the fields on the host 3270 screen, the rule of extended color mode will be applied to whole screen instead of basic color mode. Extended color mode does not have specific default colors for protected fields or unprotected fields like basic color mode does. So the foreground color of the other fields can be changed if you add extended color attribute on a field.