My Minecraft has been doing this for a good couple weeks now. I have been completely unable to join any servers and it's really frustrating. I log into my account through the launcher and run mc. I try to join a server and it says "Failed to login:invalid session (try restarting your game)" But when I close mc and open the launcher, it makes me log in again. When I try and log in, it says my password is incorrect. I have changed it an immeasurable amount of times, and I know what it is. Once I finally get logged in again, it just does the same exact thing. I haven't been able to play Minecraft for so long and it just sucks. I have tried using different versions, changing my security questions, logging out of other accounts in my launcher, updating Java, deleting and redownloading Minecraft completely, and restarting my computer many times. I've scoured the internet looking for any resolution, but have yet to find anything to fix the issue. I'd really appreciate any help you guys can offer.
When I try to connect to servers or join up on lan worlds in Minecraft it says "Failed to Login : Invalid session (Try restarting your game)". Multiplayer used to work fine but now keeps coming up with this error. Can anybody help?
Let $a, b, c \in \mathbb{N}$. Show that if $a^2+b^2=c^2$ then $gcd(a,b)=gcd(a,c)=gcd(b,c)$.  Using basic divisibility criteria I couldn't advance anything. Work done changes between reference frames? (This is not homework; a friend shared with me this puzzler and neither of us can figure it out.) Suppose you are in a plane traveling at velocity $v_1$ relative to the ground. The flight attendent pushes a cart of mass, say, $m$, accelerating it from rest to $v_2$, relative to the plane (so relative to the ground, its velocity goes from $v_1$ to $v_1+v_2$). From your perspective, the work done is then $$W = \Delta E = \dfrac{1}{2}mv_2^2$$ but from the perspective of the ground, the work done is $$W = \Delta E = \dfrac{1}{2}m(v_1+v_2)^2 - \dfrac{1}{2}mv_1^2 = \dfrac{1}{2}mv_2^2 + mv_1v_2.$$ Why are these quantities unequal?  I've seen some similar problems, like a body colliding with a wall in different reference frames, but I don't have the physics experience to tell if that question is analogous to this one. So, my apologies if this is a duplicate. :) I got multiple entry schengen visa issued by Greece. Can I directly travel from India - Qatar - Romania or through schengen state Norman Window Optimization Is "everyone" singular or plural? Which is correct?     Everyone were convinced that he would go to the game.   Everyone was convinced that he would go to the game.   I think it's "was", because "everyone" is singular, but I just wanted to check. Varying behavior for possible loss of precision Proving that a list of perfect square numbers is complete Well, I have a number  $n$ that is given by:  $$n=1+12x^2\left(1+x\right)\tag1$$  I want to find $x\in\mathbb{Z}$ such that $n$ is a perfect square.  I found the following solutions:  $$\left(x,n\right)=\left\{\left(-1,1^2\right),\left(0,1^2\right),\left(1,5^2\right),\left(4,31^2\right),\left(6,55^2\right)\right\}\tag2$$     Is there a way to prove that this a complete set of solutions? So I mean that the solutions given in formula $(2)$ are the only ones?     My work:   We know that: $$ 1 + 12x^2 \left(1+x \right) \ge 0   \space \Longleftrightarrow \space   x \ge -\frac{1+2^{-2/3}+2^{2/3}}{3}   \approx -1.07245 \tag3 $$ So we know that for $x&lt;-1$ there are definitely no solutions. There a  who has no valid parent user. It is indicated that his chat account is associated to a Maths.SE account, which does not appear to exist. The user was still able to chat. Is it normal? If it's a bug, could someone look into it?  Edit: if you browse the Google cache for users named Skullpatrol, it turns out a single series of associated accounts. The user is now named . I don't know what went wrong, maybe an account merge or something like that, but it needs someone from staff looking into it with some superpowers. I also tried to update the parent user of the chat account to this &quot;Rob&quot; profile, but the interface goes all buggy on me (works for other users, fails only for this one): Save text area to file IEEE Template. \cline error in table. Extra alignment tab has been changed to \cr I had this table working with an IEEETemplate but now when I try to build it with an IET Template I get the error that you can see on the title .. could anybody help me?  Thank very much for your time.  \documentclass{cta-author}   \usepackage{graphicx} \usepackage{multirow} \usepackage{booktabs}  \begin{document}  \begin{table}[h!]     \centering   \renewcommand{\arraystretch}{1.2}   \begin{tabular}[b]{|p{1cm}|l|c|c|c|c|}     \hline     \multirow{2}{0.3cm}{\textbf{j}}&amp; \multicolumn{2}{c|}{\textbf{k}}  &amp; \multicolumn{2}{c|}{\textbf{l}}\\     \cline{2-5}     &amp; \textbf{f} &amp; \textbf{g} &amp; \textbf{h} &amp; \textbf{i}  \\ \hline        a  &amp; b  &amp; c &amp; d &amp; e \\ \hline     \end{tabular}     \caption{Example} \end{table}  \end{document} Isomorphism involving Eilenberg-Maclane space, Tors. Let $\pi$ be a group and let $K(\pi, 1)$ be a connected CW complex such that $\pi_1(K(\pi, 1)) = \pi$ and $\pi_q(K(\pi, 1)) = 0$ for $q \neq 1$. Does there exist an isomorphism between $H_*(K(\pi, 1); A)$ and $\text{Tor}_*^{\mathbb{Z}[\pi]}(A, \mathbb{Z})$? I am using Ubuntu 12.04.  My /etc/network/interfaces file consists of:    # The loopback network interface   auto lo   iface lo inet loopback     # The primary network interface   auto eth0  iface eth0 inet static   address 192.168.1.58   gateway 192.168.1.1 network 192.168.1.0   broadcast 192.168.1.255 dns-nameservers 66.212.63.228 66.212.48.10     I ran the command: /etc/init.d/networking restart  Which responded with:   *Running /etc/init.d/networking restart is deprecated because it may not enable again some interfaces   *Reconfiguring network interfaces...   RTNETLINK answers: File exists   Failed to bring up eth0   [ OK ]     Next I ran ping google.com and received:    ping: unknown host google.com   I am not sure if my interfaces refreshed. How do I properly configure my network with my static DNS addresses? Sources missing in /etc/apt/sources.list, how do I get them back? Delete with Join in MySQL Question list on Stack Overflow is not showing new question How to use host names rather than ip addresses on home network? I've a small home network up and running and managed to set up ssh. Can anyone tell me what I need to do to refer to one computer on the network from another by host name rather than IP address (which is what I'm doing now)? Is Morocco currently safe to visit despite the Ebola outbreak? I'm travelling to Morocco over the Easter period, and while I am aware that the current Ebola outbreak is mainly in Guinea, Liberia and Mali, and would have to cross the Sahara to get to Morocco, is it wise for me to go to Morocco at this time?  What are some basic precautions I can take in the case that the Ebola virus travels to Morocco? I am trying to run Notepad as admin so I can edit my hosts file from the command line.  I have tried runas /user:(myusername)\administrator "notepad c:\windows\system32\drivers\etc\hosts" I then input my password and I get     RUNAS ERROR: Unable to run - notepad   c:\windows\system32\drivers\etc\hosts 1327: Account restrictions are   preventing this user from signing in. For example: blank pa sswords   aren't allowed, sign-in times are limited, or a policy restriction has   been enforc ed.   PS: I know if I give permission to my user account I can edit it without running as admin. But I'd like to know how to do this without having to change permissions on the hosts file. Tips to extend battery life for laptops and notebooks This question is present as a matter of historical interest.  While you are encouraged to help maintain its answers, please understand that "big list" questions are not generally allowed on Ask Ubuntu and will be closed per the .   It is possible to greatly extend the usage time of a laptop or netbook running on battery by disabling various services and installing various packages.   What tricks or tips do people have for getting an extra hour or two out of their batteries? Spring prototype beans in combination with singleton beans and dependency injection. Is there an approach that is configuration only?