It has come to my attention that some people may be seeing a page which simply says “not acceptable” when they attempt to log in to this blog. This, unfortunately, is a necessary (and hopefully temporary) security measure which has been put in place by my web host VentraIP  in order to combat an ongoing worldwide attack against WordPress installations. This security measure is outside of my control and I can not prevent this error message from appearing, however I can provide some help to overcome it.
The message should only appear if you load the login page a certain number times in a short period of time (as my web host has not made the exact number of page loads and the exact period of time available publicly, I will not disclose it at this time), and it should be noted that displaying the login page and submitting your username and password count as two separate loads of the login page.
If you see this message, your best option is to wait a couple minutes and try again. If that doesn’t help, try clearing your browser’s cache before trying again. Although the “not acceptable” page should not be cached by your browser, in my testing I found that my browser did cache it and was displaying it even when the server was trying to accept or decline a log in or log out attempt and serve up the appropriate page.
The attack against WordPress installations has been going on for quite some time now, so this security measure could be around for a while. As much of a nuisance as the security measure may be, it is far better than the alternative of having servers overloaded by automated attempts to break in to administrative accounts of WordPress installations; and even though I would like to see a greater number of loads of the login page permitted before the “not acceptable” message is displayed, I trust that my web host has not picked an arbitrary number and has instead picked a number which accurately reflects the necessary measures to limit the impact of the ongoing attack.
If problems persist, let me know and I’ll do what I can to help you log in.