DLL access denied

Access Denied: "ajax ".
Note: An unhandled exception occurs during the execution of the current Web request. Check the stack trace information for details about the error and the source of the error in the code.

Exception details: system. Io. fileloadexception: Access Denied: "ajax ".

// Upload the project to the bin directory. Ajax. dll is included. However, the above error is reported when another person is depressed.
Whenever the preceding error is reported, I only need to upload Ajax. DLL to the bin directory again.
However, if someone else transfers a new DLL to the bin directory, this error will be reported again on the page ..

I have granted all the permissions I have granted. I still don't know how it works ..

Confused ing ....

PS:
Discussion page: http://community.csdn.net/Expert/topic/4618/4618891.xml? Temp =. 1012232.