Not updated list of software

I fortnight ago to update the system are still normal today update on the problem, suggested that the wrong message is as follows :

Quote :

Guangzhou Trade Fair unable to download Http://mirror.vmmatrix.net/debian/di. . . Binary-i386/Pa MD5 checksum inconsistent ckagesIndex Unable to download Http://mirror.vmmatrix.net/debian/di. . . Source/Sources MD5 checksum inconsistent Index Unable to download Http://mirror.vmmatrix.net/debian/di. . . Ry-i386/Packag MD5 checksum inconsistent esIndex Unable to download Http://mirror.vmmatrix.net/debian/di. . . Ce/SourcesInde X MD5 checksum inconsistent Software is reading list. . . Completed W-source software to obtain the list : Http://mirror.vmmatrix.net Testing/main Packages (/var/l ib/apt/lists/mirror.vmmatrix.net_debian_dists_testing_main_binary-i386_Packages), the state - stat (2 no such documents or catalogs) W-source software to obtain the list : Http://mirror.vmmatrix.net Testing/non-free Packages (/v ar/lib/apt/lists/mirror.vmmatrix.net_debian_dists_testing_non-free_binary-i386_P ackages), the state - stat (2 no such documents or catalogs) W-source software to obtain the list : Http://mirror.vmmatrix.net Testing/main Packages (/var/l ib/apt/lists/mirror.vmmatrix.net_debian_dists_testing_main_binary-i386_Packages), the state - stat (2 no such documents or catalogs) W-source software to obtain the list : Http://mirror.vmmatrix.net Testing/non-free Packages (/v ar/lib/apt/lists/mirror.vmmatrix.net_debian_dists_testing_non-free_binary-i386_P ackages), the state - stat (2 no such documents or catalogs) W : You may need to update operation to solve these problems apt-get E : Some documents can be downloaded from the index, they may have been overlooked, possibly, in turn, use the old document indexing. -->

Please help me to see how we should do, thank you!