Upgrade issue from Debian Server Squeeze 6 to Wheezy 7 - still on kernel 2.6

Solution 1:

You're on an OpenVZ (container) based virtual machine. As a result you have no control over the kernel; it is provided by your hosting provider, and you are limited to whatever the provider chooses to provide.

If you want a different kernel, you either need to contact your hosting provider, or use something other than OpenVZ.