Have you tried turning it off, and on again?
Nobody likes it when technology doesn't co-operate, and it seems even worse when unfamiliar technology doesn't do what you expect.
If you have trouble with Slax, stay calm. We are here to help.
There are a few potential causes for this problem.
Bad Boot Disk
Both CDs and thumbdrives sometimes just don't get imaged correctly. If your Slax boot drive or disc is not booting, check it on other computers. If it fails everywhere, then it could be a bad image. Re-download, burn or unzip, and try again.
32-bit computers will not boot a 64-bit OS.
64-bit computers will boot a 64-bit or 32-bit OS.
Many people use the 32-bit version of Slax, since it's the lowest common denominator. If you are using 64-bit Slax, make sure your computer is 64-bit! And if all else fails, try 32-bit on your 32-bit machine, or 64-bit on your 64-bit machine. In other words, try not mixing-and-matching.
Since there is, sadly, no standard for what key interrupts the boot process, finding the right key to press can sometimes take a good 15 minutes of repeated trial-and-error. To make matters worse, most computers only give you a 2 to 3 second window during which you can press this magical key.
First of all, don't give up, and when you do find the right key, write it down on a sticky note and stick it to the bottom of the computer! Also, look online to see if there are any clues as to what key your particular brand of computer usually uses.
Be sure you are pressing and holding the key until you see the computer BIOS or UEFI screen. There's really no such thing as holding it down too long, so don't be shy..
If your computer shipped with Windows 8, or even was manufactured around the time that Windows 8 was nearing release, then it might have "Secure Boot" enabled. Get into the computer's BIOS or UEFI and disable it! Pay close attention; sometimes the option is worded in reverse so that you must enable the disabling of "Secure Boot".
"Secure Boot" is little more than a safety blanket that has already started to be circumvented by "bad guys". Try as Microsoft might, there's just no avoiding the fact that if a user is careless enough to download and install malware, then a computer is going to be infect. "Secure Boot", anti-virus software, and even Linux, cannot change that fact.
If your computer is a Mac, then you may have a model that locks you out of booting into another OS. There are (currently) sometimes ways around this, but Apple is making it more and more difficult to run anything but Mac OS or Microsoft on their hardware.
When you see the boot screen of Slax, press the Tab key. This provides you with kernel arguments, which will look very cryptic, but all you have to do is add nomodeset at the very end, and then press Return.
What is happening in this situation is that Slax is attempting to initialize your computer's video card, but your computer's video card is not responding, usually because of driver issues. The option of nomodeset skips that step during boot, and should result in a graphical desktop for you.
Since Slax has to determine its environment with each boot and then also try to make your personal choices adapt to what is a new environment, too much customization can sometimes confuse Slax.
Try running the bootinst batch or script file that you ran on your thumbdrive when creating your boot drive. That sometimes helps re-set things.
If that doesn't help, de-select the Graphical Desktop option on the Slax boot screen. This should allow Slax to boot to just a terminal window. Once there, log in if necessary (your username is root and your password is toor), and then issue this command-
mv ~/.kde ~/.kde-broken && reboot
That should fix everything, although your customization will be lost.
If you are running from CD and have placed modules on a thumbdrive, but they are not loading, then you are probably issuing the command to load them incorrectly.
First of all, make sure that your terminal is in the directory that contains all of your modules. Also, make sure you are entering the command exactly as detailed in the saving modules section of this site.
If you are using this site's cheat script, then you should make sure that the script is executable. To do this, right-click on the loader.sh file and click the Permissions tab. Make sure the Is Executable box has a checkmark in it.
If your modules still do not load, then possibly you have not downloaded them correctly, or maybe they are corrupt. Re-download the modules and try again.
Keep in mind that you do have to load the modules upon each boot, when running from CD, because nothing on the CD is telling Slax to load the modules, and even if it did, Slax would have no memory of where to find the modules anyway.
The applications chosen for Slax, and most of them on the Slax site available for download, tend to be pretty hearty. If an application is crashing, it might be because of some file that you are trying to use within that application, whether it's a spreadsheet in some proprietary format, or a video file in a strange codec, or so on. Investigate online whether those types of files are supported by the application you are attempting to use.
If you feel sure about the integrity and support of your files, launch the application from a terminal and use it as you normally would. Try to notice what activity you are doing when the application crashes. Once it crashes again, post a polite question online regarding the crashes, and copy and paste the last 20 lines or so of the messages that the application sent into the terminal. Usually the best place to ask for help with application crashes are in the application's user forums.
If Slax itself is crashing such that the screen freezes and no application will run at all, then there are a few potential reasons.
Slax is small, but if the computer you're on doesn't have enough RAM then the more applications you run, the more you use up the available RAM. Slax may be either stalling or actually crashing because it needs more RAM than what is available.
To fix this issue, you would need to add more RAM to the computer, or perhaps mitigtate how many applications at one time you are using.
Some models of computers cache data in memory and then fail to clean out that cache even after a reboot. If Slax is crashing and you have plenty of RAM, then try shutting down and then unplugging the computer. Leave it unplugged for a few minutes so that the charge is depleted from the hardware. Then plug it back in and start it up again.
Another problem could be that the memory chips are actually going bad. There are memory tests that you can perform from repair discs, but it takes a long time and may not be worth the trouble if the machine you are using is just a temporary one anyway.
Both of the memory issues should be specific to certain computers. If Slax is crashing across every computer you are using it on, then the problem is more likely a boot drive issue.
Bad Boot Disk
Both CDs and thumbdrives sometimes just don't get imaged correctly. If Slax is crashing consistently, then it could be that there is a corrupt file somewhere on the drive that is causing the system to crash whenever it is called upon to be used.
To rule that possibility out, try the same Slax boot disk on another computer and see if it crashes. If it fails everywhere, then it could be a bad image. Re-download, burn or unzip, and try again.
Slax is designed to be a temporary OS. While you can, of course, do pretty much anything with Linux, it is not a good idea to install Slax.
If your experience with Slax is inspiring you to install Linux onto a computer, you probably won't be sorry, regardless of which "flavour" of Linux you choose. But if you are looking for a Slax-like experience, you might try either Salix OS, Open SUSE, or Mageia. All of these are very good Linux distributions with a nice KDE desktop and a built-in software installer so you won't have to go and search a website for installable modules.