A Samsung phone, including a galaxy, can freeze for various reasons. This can happen on the splash screen, on the logo during power-up, with a non-removable battery and a removable one.
Then he does not react to anything. Firmware may be the culprit installed applications, insufficient memory, and hardware failure.
I now have a Samsung a5 and a3 with a non-removable battery. In the course of use, I noticed that most of all it freezes if it has not been rebooted for a week.
I put it on Sunday at 3 o'clock in the morning and there was one less problem, but it can hang when turned on on the logo. How to fix it?
This is most likely a problem not with the phone, but with the system. If we have the opportunity to enter the factory reset mode, then use this.
Restoring factory settings when a Samsung phone freezes
Restoring to factory settings deletes restores old version android. All data will be deleted, including temporary files.
If you have the opportunity to run working condition, then the reset can be performed by entering the settings, but if the hang occurs on the logo, this is not possible.
Then turn off your Samsung phone completely (preferably by removing the battery for a few seconds).
Then insert the battery, but do not start the phone in the traditional way, but hold down and hold the key combination: Power (Power) + Home (House button at the bottom of the screen) + Volume Up (volume increase).
Hold them down until the main recovery screen appears on the display. Then you can release the buttons.
When the system asks if you really want to delete all data and restore factory settings - confirm your choice.
All data from internal memory phone will be deleted and the settings will be reset to default.
Now in recovery mode, select "Reboot system now" (reboot the system now) - now your phone should work correctly and not hang on the Samsung logo.
Reasons for the slow operation of the Samsung phone and frequent freezes of the Android system
Slowness has many reasons: a large number of applications, which leads to a lack of device RAM, the use of animation in screensavers, widgets, wallpapers and wallpapers.
Also, the reason may be in the firmware update - there may be a conflict with installed programs(most common cause freezes). How to fix it?
If you have installed a large number of applications, check if there are unused ones on your phone and delete them.
Check your phone for safe mode. If this works correctly, then boot the device into normal mode and uninstall downloaded apps one by one until the problem is fixed.
Also remove animated wallpapers and widgets and watch your samsung phone work.
The developers of Samsung devices tweeted this: “Slow performance may be caused by a lack of free RAM. End all background processes."
It means to release RAM and remove applications from the phone that are suspected of high resource consumption.
When performance deteriorates (slow launch of programs, delay in scrolling, transition between menu items), sometimes you even want to hit your phone against the wall with your phone.
Only you instead just try to review all the programs on the memory card - each program takes up space and negatively affects performance.
Therefore, feel free to delete unnecessary ones, and not only applications, but also accumulated garbage.
Take a look at the gallery and determine if there are any unnecessary photos and videos. Also, don't skip the Downloads folder, where there is usually a lot of junk. Check memory, especially cache. This data can also slow things down.
Should I change my Samsung phone if it freezes
Even if after full reset android phone freezes, so to speak, nothing helps, then perhaps it is outdated and does not meet modern requirements.
There are special programs for evaluation, such as Antutu Benchmark. Install it from the play store and test your samsung android.
If the test shows scores less than six to seven thousand, then you should think about finding and choosing a new device.
A good result is at least 15-20 thousand points and this is only a minimum, especially for launching games. Good luck.
Android is the most used, multifunctional and powerful operating system, on the basis of which an unlimited number of high-quality, interesting and affordable applications have been created. Due to its versatility and huge demand, it is successfully used for the software of smartphones, tablets, netbooks, smart watches, smartbooks, TVs. But, even with the most proven shells, there are minor difficulties, from which even this system is not immune during use. Therefore, we will look at what to do when problems arise with WiFi connection on your Android device. Today we will find the answer to the question why Wi-Fi does not turn on on android?
Reasons and solution
WiFi on your phone or Android tablet may not work for several reasons. It should be noted that not only owners may face this tablet computers, but also people using Cell phones, based on this popular system. How to be users if wifi does not turn on samsung devices, we will look for the cause and eliminate the root of the problems. 
- One of the root causes if Wi-Fi stopped working on Android, which is extremely rare, is an incorrectly set date and time. To fix it, just go to "Settings", set the correct date and time, taking into account the time zone.
- The second and most common problem is changing the password when automatic connection to the network. That is, the password has been changed by the user, but android system still doesn't know about it. To fix this problem, using the interface or hot keys, go to the connection settings WiFi networks, delete the profile with which the connection was previously established and create the connection again, select from the list available connections your own, enter the necessary characters in the window that appears. Further, the connection to the password-protected network will occur automatically.
- Software failures ( Software) is the third of possible causes when Wi-Fi on Android stops connecting. To do this, use the Wi-Fi Fixer utility, created specifically to solve this problem. Without making any changes in the program settings, download and install this application. After installing the utility, information about the current status of the device will appear, and all devices that have ever been connected will be displayed in the “Known” tab. Then we reboot the smartphone or computer tablet, try to make the connection again.
- The fourth problem, if Wi-Fi does not work on android, is a failure in the settings. To bypass it, you can reset the settings to factory settings, with further restoration. Go to "Settings" select "Backup and reset", click "Reset settings". Or we do a complete " hard reset”, but then all data is deleted, that is, the device will be the same as after purchase.
Sometimes users install inappropriate android firmware, as a result of which the correct operation of radio modules is disrupted, including the wifi module on Samsung phones or tablets. The way out in this situation is to install or update the basic firmware on the Samsung.
Those viruses again!
One of the most unpleasant reasons when wi-fi does not turn on is the impact malware, the so-called virus programs, on the operation of the radio modules of the device. To eliminate viruses in the phone, you need to do a deep scan with the built-in antivirus.
Setting up the router
The venerable seventh place is occupied by a pop-up error when connecting to Wi-Fi - a failure or incorrect configuration of the router. The elimination of this error is carried out in the router settings. How to do this can be found in the instructions for the device. This is especially true if used home network. In the control menu, select "Settings wireless network". We change the parameter to "Auto", in the line "Channel", and the line "Mode" to the parameter "11 bgn mixed". Turn off MAC address filtering to make sure that the router does not filter the addresses of connected devices. Let's try to connect.
And now it's time for the master
If none of the above methods helped, then the problem is in the radio module itself, wifi will not work until the chip is soldered. In this situation, best solution, there will be a warranty claim in service center(for example, Samsumg) or to a competent and proven computer wizard.
It must be remembered that any intervention by incompetent persons in the operation of the system, even when solving the problem when Wi-Fi is not connected, creates a huge risk, turning your favorite gadget into a useless piece of plastic, for the resuscitation of which will take significant financial costs and your nerves.
According to an unspoken tradition, I will leave a video instruction, perhaps it will help you restore wifi on a Samsung tablet or phone.
Video instruction
First of all, a telephone is a means of communication, and only then a multimedia player, a tool for surfing the Internet, a camera, etc. And if the smartphone does not accept SIM cards, its main function will be unavailable. Sim card problems samsung galaxy may arise for various reasons. Some of them can be eliminated on their own, while others require more professional intervention. Let's look at why Samsung does not see SIM cards, and what to do in a particular case.
Top Causes of SIM Card Issues on Samsung Phones
There are a lot of factors leading to the fact that the device does not see or cannot recognize the SIM card. However, all of them can be grouped into three groups:
- Mechanical failures of the mobile device. They occur when the card is frequently removed / inserted into the SIM slot, the device is damaged as a result of a strong blow or moisture penetrates under the case.
- Problems related directly to the SIM card. May be due to the presence of printed circuit board scratches, chips and other mechanical defects, the expiration of the SIM card or its blocking by the operator.
- Work failures operating system or installed software. Samsung may not see the SIM card after its software shutdown, due to the installation of unofficial firmware, or through the removal of the IMEI number.
Let's consider each of options in details.
Mechanical damage to the mobile device and how to eliminate them
If there are problems with the operation of the SIM card, the first thing to remember is whether the phone has been subjected to any external influences. So, if you dropped it, there is a possibility of failure or soldering of a power amplifier, microcontroller, connector or other module. In such cases, it is better to contact the service center.
If there were no prerequisites for a Samsung breakdown, try the following:
Troubleshooting SIM Card Issues
If you have determined that the SIM itself is the source of all the troubles, it is recommended to act in the following order:
Software failures
If you are the owner of a dual-SIM Samsung and the SIM card is not visible on only one of the connectors, see if the second slot is enabled in the device settings. Desired function located in the "SIM card management" section. 
There are cases when, after a smartphone is infected with a virus or its self-firmware, NVRAM is damaged on it - non-volatile random access memory. This is where the IMEI of the mobile device is stored. When you erase it, Samsung will not detect SIM cards.
To fix the problem, you will need to repair the IMEI. This can be done through the engineering menu:
After restart Phone IMEI recover and everything should work. If this did not help to get rid of the problem, you will only have to reset all settings to factory settings or reflash the smartphone via PC and Samsung program Kies.
Today we will talk about one problem that can sometimes arise for owners of Samsung smartphones, including the Galaxy series (S4, S5, S6, S7, S7 Edge, etc.). This is a Camera Failed error in English. It occurs when you launch the Camera app. As a rule, this problem is easily solved.
Here's what the error looks like:
This is the English version:
What to do? Consider some of the most relevant options.
Smartphone reboot
The first thing you should do is reboot your device. Yes, at first glance, this idea can be called stupid, but practice shows that it is this simple action that most often helps to solve software failures.
Deleting data and clearing the cache of the Camera app
If the method above did not help you, the next step is to clear the cache and data of the Camera application.
To do this, go to settings. In the settings, find the application manager.
Find the Camera app and open it.
See the Clear Data and Clear Cache buttons? Click on them one by one to delete the data.
Check if the camera is working.
Clearing gallery data
Do the same for the Gallery app.
Some of the owners Samsung phones may encounter a situation where their phone refuses to boot on reboot, and the screen displays the message “Downloading… Do not turn off target”. Pressing various keys does nothing, the phone does not react in any way, and the user has no idea what to do. In this article, I will try to shed light on this problem, I'll tell you why this inscription appears, as well as explain how to get rid of Do Not turn Off Target Samsung on your mobile device.
The above screen that says "Downloading... Do not turn off target" in "Downloading... Do not turn off target", which translates to "Downloading... Do not turn off the target device" is the downloading mode (downloading mode), which is used to implement firmware (installation of the OS and its elements) mobile devices from Samsung. As a tool for this purpose, special program called "Odin", designed exclusively for flashing mobile devices from this South Korean brand.
Usually, to enter this mode, you need to hold down the power button and the volume down key, and then, after entering the technical mode, also press the volume up key. So you get into the “downloading mode” (“odin mode”), the inscription I quoted is displayed on the device, and the device itself enters a state of readiness for firmware and connection to a PC.
Because the regular user does not know what to do in this situation, the device will remain in the Do not turn off target state until its battery runs out. After the device is turned off and the user charges it again, the device will again work in normal mode.
In addition to the cause of "crazy hands" accidentally running "odin mode" on the device, there are a number of other determinants that can enter your samsung smartphone to the specified mode:
How to Fix Do Not Turn Off Target Error
If your phone accidentally enters Do Not mode turn off Target, you don't have to wait hours for the battery to run out. Just hold down the power button for a while (10 to 30 seconds) and your phone will reboot normally.
Also, a good alternative would be to simply remove the battery from your device (if it is removable), some experts recommend also removing the SIM card along with the battery. Wait a few minutes and then put the battery and card back.
Usually, these actions are enough to restore the normal operation of the device. If these techniques were ineffective with the Do Not Turn Off Target mode, then we are dealing with a serious dysfunction of the device, and you need to do the following:
- Try resetting your phone to factory settings. I immediately warn you about the loss of user data on the device after performing this action, but if the usual reboot of the device does not help, then you can try this tool. Hold down the power and volume up keys of the device, wait for the image to appear on the screen, and then release the keys. You will fall into recovery mode(recovery), there you need to select the option wipe data / factory reset and wait for the process to end;
- If resetting the data to the factory settings did not help, then you should consider flashing your device. Please note that this action should be carried out by a professional, and it is advisable to use official firmware from the developer
- It is also worth contacting the service center with a description of the problem. Perhaps your device is damaged at the physical level, and various software manipulations here will simply be ineffective.
Visually, how to remove the Do Not Turn Off Target inscription can be seen in the video.