How Do I Fix No Available Terminals Error in Cygwin

I use Cygwin's mintty based shell all the time. Once in a while this error occurs:

Error: Could not fork child process: There are no +available terminals (-1)

The solution I found is:

Windows-R
cmd
cd \cygwin\bin
rebase-trigger full
cd \user\xxx\Downloads\cygwin
setup_x86.exe