Crystal report 10 ????

I have a problem with crystal report 10. I have created a report with a database file is a text file. Then I added it into my project in VB .NET 2003. I called it in a form. And I got the message below:
"Error in file <path> Buffer to small for string or missing null byte". With <path> is the path of temp file.Then I move this report file into drive c:\, It works. I don't how to solve this.
Do you have any idea?

Thanks