Error check won't let me enter correct amount

Final error check turned up a problem on the Capital Gains (loss) worksheet.  It says "Accrued market discount should not be 0.  Enter amount disallowed under wash sale rules or leave blank if entire loss is disallowed."  The data box has "0." in it.  My amount disallowed was one cent.  I'm not able to enter any number in the box much less the 0.1 that need to go there.