. Net compilation errors in debug mode

Recently, I don't know why XP SP2 is installed or what other reasons. During vs.net development, as long as the project is set to debug compilation, an occasional error is reported. The error message is similar to the following:

"Create the debugging information file" E: \ source \ businessrule \ OBJ \ debug \ businessrule. an unexpected error occurred in PDB -- "E: \ source \ businessrule \ OBJ \ debug \ businessrule. PDB: AnotherProgramThe file is being used and the process cannot be accessed ."

The solution is to exit vs.net, delete the file that is prompted to be occupied, and re-open the project. This is the right time.

Why? Is there a better solution?