# Trial version Mathematica 10.4 corrupts previous versions [closed]

I've downloaded the trial version 10.4 to test it and compare it to previous versions. I still use versions 8.0, 9.0 and 10.0. During the installation of the trial version, I didn't permit the remove of the older versions. But after the installation and the opening of the trial version, my version 10.0 has been erased and the other two are now trial versions with limited access to some commands. The installation of the latest trial version corrupts the previous ones !

Is this a bug ? How can I recover all my previous versions for which I've paid ? Why does the latest trial one interfere with the others and corrupts them ? What's the purpose of Wolfram to act like this ?

I'm upset, totally upset !

• These are all valid questions, but you should direct them to Wolfram Support. This forum is not run by Wolfram, nor connected to them in any way, although some Wolfram employees participate as well. Licensing-related questions in particular are explicitly off-topic for this forum. – MarcoB Mar 26 '16 at 13:05
• That is weird, and really annoying. I hope you get this sorted out quickly. Possibly the installer deleted or overwrote your existing licensing files. Maybe you have a back-up? Do the earlier versions give you the menu option to Enter Activation Key? What happens when you try that if they do? – Mr.Wizard Mar 26 '16 at 14:03
• Evaluate SystemOpen@FileNameJoin[{\$UserBaseDirectory, "Licensing"}] in Mathematica. It will open the folder where the license file, named mathpass, is. First make a backup of this file. Then open it with a text editor and inspect it. It may have several lines, each corresponding to a license key. Remove the one with the trial license and leave the rest. See if it works now (restart Mathematica). – Szabolcs Mar 26 '16 at 14:56
• In the mathpass file, you should see two or more lines. One of the lines is your license. The other is the license for the trial version. Move the trial version of the license to the bottom. It is probably at the top of the file. This will cause copies of mathematica to first try your actual license and then only try the trial license when that ones doesn't work. – Searke Mar 26 '16 at 15:59
• Sorry folks, I didn't mean to annoy you with my problems here. Thanks to them who replied. I followed the recommendation of Mr.Wizard and rewrote my Activation Key. It worked for the versions 8.0 and 9.0. It didn't for the 10.0 for which I've no Activation Key. Then I tried the recommendation of Searke. I got the folder of the License, but it is empty. I'll wait till the Wolfram Support Department helps me. Thanks to both of you, I recovered two of the three versions already. – Jean-Pierre Mar 26 '16 at 18:26