在ISE14.7中遇到管脚无法匹配，点不进去，有没有什么方法

点击I/O pin planning（planAhead）postsynthesis 进不去，然后报错显示ERROR: no available run directory could be found. You can use Project -> Cleanup to delete existing planAhead_run directories in the project working directory and try again if you are not running multiple copies of planAhead.。不知道什么原因。