请教使用ChipScope时出现的问题，急~ ChipScope, 请教

hxrcsu

Successfully read project E:\project\a.cdc
copy E:\project\a.ngc => E:\project\_ngo\a_cs_signalbrowser.ngo
<ERROR> ReadAsXdm Failed for E:\project\_ngo\a_cs_signalbrowser.ngo
<ERROR> XDMDesign::getBlockForPath() - Design does not exist
<ERROR> XDMDesign::getBlockForPath() - Design does not exist
Could not parse design. Could it be encrypted or corrupt?

在用ChipScope的时候出现上述问题，之前用的时候都是好好的，不知道咋冒出这个错误了，请教一下各位大侠啊，谢谢啦！