Error message

[zxc]

Happy new year everyone!

I am running a HEC-RAS 3.0 unsteady mode. After the program finished the "Geomentry processor", a small window pops up sayiny

Htab.exe has generated errors and will be closed by windows
An error log is being created

But when I click "View computation Log File", it says

xx.bco does not exist

Actually this error acts just like a virus. I have finished one running sucsessfully and saved the project. Then I copied the needed files to a new folder, and changed input flow hydrograph, the error message mentioned above appears. So I deleted the new folder and went back to the folder where the "good" project saved, just found the same error occured to the "good one" again. I also tried restart the computer, not working.

So could anyone giev me an idea what's the possible here?

Thanks a lot

David C.