I'm trying to upgrade from 12.04 to 14.04 and am encountering problems. I'm working from 12.04.  Downloaded the 14.04 iso file.  Used the Startup Disc Creator App.  However, when I try to boot from USB, I get a "Boot error" message. I've tried booting with the USB drive in all 4 USB ports.  I've reformatted the USB drive.  I've re-downloaded the iso file.  Keep getting the same results.   Frustrating because it worked fine when I loaded 12.04 using this same procedure on the same computer (Toshiba Satellite with AMD 64 processor).
I tried to use the usb-creator.exe from Ubuntu 10.10 desktop i386 ISO image and it does create an USB stick that doesn't boot. When I try to boot from it I get:     Operating System not found.   I try to do this from Windows 7 x64. I'm not looking to create a live Ubuntu media, only an installation USB disk.  I repeated the process several times and I even tried to reformat the USB drive (FAT32), no success yet.  The USB stick is a 8GB one.
I have been hit with a homework problem that I just have no idea how to approach. Any help from you all is very much appreciated. Here is the problem  Prove the equation: $a^{\log_b c} = c^{\log_b a}$  Any ideas? How to delete a file in Windows with a too long filename? My wife has several files and folders that somehow ended up having filenames that have caused them to be undeleteable (can't be deleted) by normal means or via the command line. I believe the filenames are too long due to the depth of the folder structures. Does anyone know of a good utility for cleaning up files like this? I've imported several shapefiles which where exported from a Mapinfo .tab. Several  .tab-files are imported resulting in 20+ layers. Afterwards I want to export it to GeoJSON; but I'm reluctant to select each layer and export it manually. Is there a way to merge all the layers into one using QGIS? character "5" repeated in text fields, and system freezes I am running Ubuntu 15.10, with the latest updates.  When I type in a text field (google search, type name of file, etc..) the number 5 gets typed on its own and it keeps repeating until I press ESC and when I try to continue typing the number 5 resumes filling in the text field.  I have tried to set the keyboard repeat to zero, but does not help.  This does not happen all the time, sometimes if I shut down the computer it then behaves normally when I restart it, other times the computer becomes useless because I cannot type in any of the text fields.  Thanks Sal How can I install an app given only its APK file? Title of 80's movie: future-era timetraveling humans go extinct and rescue/kidnap todays air crash victims What is the title of a 80's (i believe?) movie where humans in the far future are going extinct, and are aquiring new humans by going back in time to todays world, kidnapping air travelers that are known to have died that day, from the flying passenger aircraft just before its crashing.  A key visual:    Inside a hangar, a time portal opened, and a tail of a (flying) passenger aircraft extruded into the hangar where a stairs provided access to the back door of the aircraft.  The kidnappers made sure the surviving passengers remain seated and would forget about the whole ordeal. Kidnapped humans got replaced by lookalike dummies, including things they had on them. They tried hard not to alter the timeline. I'd like to know whether, given a system, there's a way to obtain all the conserved quantities. For instance if the system consists of electric and magnetic fields, the fields must satisfy Maxwell's equations. These equations are invariant under many transformations (Lorentz transformation, rotations, spatial and temporal translations, etc. By the way is there a way, maybe from group theory, to find all the possible transformations that leaves the equation(s) invariant?) which imply as many conserved quantities thanks to Noether's theorem. In wikipedia I can see an equation that seems to give all the conserved quantities () but it involves the Lagrangian and I'm not sure whether the formula is valid for all systems whose Lagrangian is possible to obtain. sed one-liner to delete everything between a pair of brackets? I am working with some text that is full of stuff between brackets [] that I don't want. Since I can delete the brackets myself, I don't need the one-liner to do that for me, but I do need a one-liner that will remove everything between them.  What about parentheses () instead of brackets? I'm finishing professional school and over the years have acquired a pile of notes and articles that I'd like to hang onto.  I'd like to add to them and create sort of an archive of article and files that may be useful down the road.  I'd also like to organize this collection of files not only by simple grouping but also with tags.  I feel like that will make searching through them years later much easier.  Suggestions on software that would be good for this?  Just a general file manager, something that uses tags that can be attached to each file? How do you normalize a zero vector Simple examples of uncorrelated but not independent $X$ and $Y$ Way to detect frozen video with ffmpeg? Is there a way to detect frozen video with ffmpeg? I only need to know if there are rather large regions of frozen video, say 10 seconds or more.   I'm familar with the  filter.   Maybe you could first difference adjacent frames, then use blackdetect to tell whether the difference has not changed? I'm not sure how to perform the difference though. Can moving tables to another MySQL database help performance? I want to know if I using different databases can help performance.  I have one big table support_chat with more than 5 million rows. I need to scan this all the time (3s with ajax) to check new messages on support.  If I move this table to another database in the same computer, can it help anything? (let users, sells, comments table faster)  For example:  db1  users table sells table comments table support_chat table // move this table to db2   db2  support_chat table   They want to keep old things due legal reasons, to have a user support history. new array.sty and colortbl.sty incompatibility? Bezout's identity in $F[x]$ Let $F$ be a field and $F[x]$ a polynomial ring. Let $p(x)$ be an irreducible polynomial.  Show that $\gcd(p(x),q(x)) = 1\Longrightarrow \exists r(x),s(x)$ such that $r(x)p(x)+s(x)q(x) = 1$.  I know the proof for Bezout's identity for , but this proof uses the notion of absolute value, which cannot be applied to a polynomial ring.   I am thinking about a way to prove the statement: Use the Euclidean algorithm to compute $\gcd(p(x),q(x))$ and show that the result is $1$, and somehow go backwards to obtain $r(x)p(x)+s(x)q(x) = 1$, but it is a bit messy, and I'm not yet able to see it completely.  Please offer some help. If you have some other methods, that would be great, too. How do I tackle this combinatorics problem about married couples around a table? After updating to 2.81, my previous works (done in 2.80) doesn't show colors Polygon Touch detection Google Map API V2 What is the best way to convert a JSON code as this:  {      "data" :      {          "field1" : "value1",          "field2" : "value2"     } }   in a Java Map in which one the keys are (field1, field2) and the values for those fields are (value1, value2).  Any ideas? Should I use Json-lib for that? Or better if I write my own parser? How do I start with in-camera JPEG settings in Lightroom? I'm a novice shooting in RAW and find that half the time my camera JPEG images come out better than my Lightroom tweaks to RAW files.  So to give myself a better start I'd like to apply the JPEG settings that are applied automatically by the camera to my RAW files in lightroom so that initially my RAW files look exactly like the JPEG files.   How can I do this?