when i build the example project complete and login http://xxx.xxx.xxx.xxx/bioinfo_ops/. it popup a window and shows that"A user name and password are being requested by the site". Then i key in root and password.The browser shows "internal server error"

http://xxx.xxx.xxx.xxx/bioinfo/
http://xxx.xxx.xxx.xxx/
are work well

The user name and password required by your project are not root + its password, but an account you make on the project + its password. Compare it to the account you made to get access on this forum. It's such a (BOINC) account that you need.

And that's either done through the front page of the project->Create an account (http://xxx.xxx.xxx.xxx/create_account_form.php), or through BOINC Manager->Add project->add URL to your project->New user->Fill in email + password. If done through BOINC Manager, the account's name will be the name of the operating system account that you made the account with. So if you're logged in as Admin, it'll be Admin.

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