Unable to connect to webserver from outside
setting up apache2 webserver -- differences between behaviour within my intranet and outside
Just doing this for revision, seems much harder than it should be, should I use $x=\tan u$ ? Any help appreciated. How to customize the ubuntu gnome 3 desktop? This is maybe a stupid question, but how can I choose my own background image on ubuntu gnome 3?? I click on Settings -> Background -> then I click on the current background preview to change it but I see only the defaults images! No + symbol to add or something. On the 'Pictures' tab there is nothing to select, I get an empty white page? I am running ubuntu gnome 13.04 3.9.6-030906-generic.  Thanks! Evaluation of ratio of two binomial expression iPhone 6s with iOS 12.4 not connecting to MacBook Pro mid2015 with macOS 10.14.6 I am using an iPhone 6s with iOS 12.4 and a MacBook Pro mid2015 with macOS 10.14.6. Since recently (I am not exactly sure when it started), I cannot charge the phone with my computer anymore. As soon as I plug the phone in, it will play the charging sound repeatedly. The right-hand side port sometimes works, the lefthand side port never works. When I connect my old iPhone 5 (using the same cable), it charges without any issues. My iPad mini 4 shows the same issue.  Sometimes the "Do you trust this computer" setting flashes on the phone and disappears before I can click anything.   How can I fix this?  Update 1  Sometimes I get the Software Update dialogue in macOS. After approx. 2 minutes it shows the following:     Update 2  For some reason the issue disappeared for a while but is back now. Disabling "Settings" > "Touch ID &amp; Passcode" > "USB Accessoires" seems like it makes the problem a bit less bad, but not go away.  Update 3  This is driving me crazy. I upgraded to Mojave 10.14.3 mostly to get rid of the issue. It persists. Some more random information: Before logging in (Filevault pre-boot authentication), the phone will charge fine. Only when a user account is loaded, the issue appears. The likelihood of a successful connection increases with the battery state of the iPhone. Workaround 2 in my answer below suggest that this a "Trust issue" from the iPhone's side. I suppose the solution will have to be hidden somewhere there...    What I tried so far (will update):   Reset Privacy settings on iPhone Different (original, almost new Apple) lightning cables   Remove and add "iPhone USB" in Network Settings  SMC reset (), PRAM reset Upgrade to latest iOS 12.4 and MacOS 10.14.6 I'm using a Samsung I9000 and I have some annoying apps that came pre installed by the phone vendor, like a music store, a custom web browser and other memory leaking apps.  Those crappy apps can't be uninstalled neither by Manage applications tool, nor by editing the apps tiles in the front menu.  I guess I have to be a root user or something to get rid of those apps, but I don't know how. Currently, Stack Exchange’s Markdown parser only allows four-space indents to represent code blocks:      // some code     // another line of code    and other Markdown implementations allow for an alternative syntax, that doesn’t require indenting each code line:  ``` // some code // another line of code ```   This is much more convenient to type out. It would be super useful if Stack Exchange could support this syntax.    By extension, this syntax also allow you to specify the source language right after the opening ```:  ```js // some code // another line of code ```   …which would then enable syntax highlighting for that specific language. Although it’s interesting metadata, I don’t think this feature is needed on Stack Overflow, as the syntax highlighting library works pretty well for various languages.  So, even if you would allow this syntax but ignore the ```language, this would greatly improve my productivity on Stack Exchange.  What do you think?  The moderators are currently collecting feedback regarding this feature, so please post a comment with your thoughts. Good idea? Bad idea? Don’t really care? What do you think are the benefits/drawbacks? Experiences? Let them know! Thanks! Update Windows 8 Enterprise to Windows 8.1 Enterprise KMS activation So it is shown that volume license packages of Windows 8, like Pro and Enterprise, are unavailable for upgrading.  I received a link last night to download the Windows 8.1 Enterprise 90-day Evaluation, but it will replace my current Windows 8 Enterprise version.  Is it known when these versions will become available for upgrade? I've been waiting patiently for weeks to get this upgrade.  Thanks. I can't get grub menu to show up during boot What is the EV scale? I have seen an "EV" (exposure value) scale that's sometimes used to express a camera's exposure settings, or scene brightness. How exactly does this scale work? I've noticed that apps (such as Google Contacts Sync) that have been disabled using the stock Android (KitKat) app manager still show up as running when using process observer tools.  This is true even after the device has been rebooted.  Why are disabled apps still running?  Is there an effective (and safe) way to actually disable them?  Solutions requiring root privileges are acceptable.   (Note that for the specific example above, you can tell Android not to sync your contacts, but it still runs the Google Contacts Sync process.  But let's not dwell on that example... it's just an example.) Number of points on a line in a finite projective plane I've been reading some proofs regarding finite projective planes of order n, and often they start out by assuming that each line contains n+1 points. Is this a fact that follows from the axioms for finite projective planes? Or does this relate to the order of the finite field being projected? (for example in the Fano plane, does the fact that each line contains 3 points follow from the fact that there are 3 elements {0,1,2} in Z_2?) I haven't been able to find a clear explanation of this (clearly I do not yet have a solid understanding of how such planes are constructed). If someone could enlighten me that would be excellent. The browser's "Back" button cause problems with the review buttons What happened to the idea of getting inbox notifications for favorited questions? found a 1994 uncashed profit sharing retirement plan check I found an old un-cashed check dated 1994 for $487 from my Xerox Retirement plan with no expiration date. Can I still cash it? Is the product of two Gaussian random variables also a Gaussian? Say I have $X \sim \mathcal N(a, b)$ and $Y\sim \mathcal N(c, d)$.  Is $XY$ also normally distributed?  Is the answer any different if we know that $X$ and $Y$ are independent? If $E$ has Lebesgue measure $0$, must there exist a translate such that $E\cap E+x=\varnothing$? If $y\in E\cap E+x$ then $y=h=h'+x \implies x=h-h'$ for $h,h'\in E$. Likewise, if $x=h-h'$, then $h\in E\cap E+x$. So that $E\cap E+x$ is non empty iff $x=h-h'$ where $h,h'\in E$. Thus, if there exists a real $x$ which cannot be expressed as above, the result is proven. The problem is I cannot prove that such an $x$ must exist. I have tried assuming that all real $x$ are of that form, but that gives me nothing except that $E$ must be uncountable and unbounded. Any hints? I currently have the Geometry Dash lite version and I want to buy the full version. Can I login with my account of Geometry Dash lite and keep everything I already had? It would suck if I had to redo everything. What is the difference between sourcing ('.' or 'source') and executing a file in bash? What's the difference between executing a script like this:  ./test.sh  and executing a script like this:  . test.sh?  I tried a simple, two-line script to see if I could find if there was a difference:  #!/bin/bash ls   But both . test.sh and ./test.sh returned the same information. Operation not permitted turning off airplay mirroring How to apply a macro to each column of a table