Hi Marko,
Thank you for posting your query in Microsoft Community.
This could be due to several reasons and to diagnose the issue, let's try the following methods and check.
Method 1: Try booting into Safe Mode and do a System Restore to early point in time before you started experiencing this problem.
Step 1: To use a Safe mode option, follow these steps:
1. Restart your computer and start pressing the F8 key on your keyboard. On a computer that is configured for booting to multiple operating systems, you can press the F8 key when the Boot Menu appears.
2. Use the arrow keys to choose Safe Mode in Windows Advanced Options menu appears, and then press ENTER.
Step 2: System restore will take your computer to pervious state when it was not facing such problem, this can be done by selecting the proper restore point.
To restore the operating system to an earlier point in time, follow these steps:
1. Click Start, type system restore in the Start Search box, and then click System Restore in the Programs list.
If you are prompted for an administrator password or confirmation, type your password or click Continue.
- In the System Restore dialog box, click Choose a different restore point, and then click Next.
- In the list of restore points, click a restore point that was created before you began to experience the issue, and then click Next.
- Click Finish.
You may refer to: How to repair the operating system and how to restore the operating system configuration to an earlier point in time in Windows Vista (information holds good for Windows 7 as well)
Important: When you use System Restore to restore the computer to a previous state, programs and updates that you have installed after that date are removed.
If the above method did not resolve your issue then, try the below method.
Method 2: Perform Startup Repair on your computer with Windows 7 installation disc
- Insert the Windows installation disc into the disc drive, and then start the computer.
- Press a key when the message indicating "Press any key to boot from CD or DVD …" appears.
- Select a language, a time and currency, and a keyboard or input method, and then click Next.
- Click Repair your computer.
- In the System Recovery Options dialog box, choose the drive of your Windows installation and click Next.
- In the System Recovery Options dialog box, click Startup Repair.
For more information, please refer to: A Stop error occurs, or the computer stops responding when you try to start Windows Vista or Windows 7
If you are unable to see the option "Press any key to boot from CD or DVD …” then follow the steps mentioned below to change the boot order in bios.
**Bios Disclaimer:**Modifying BIOS/complementary metal oxide semiconductor (CMOS) settings incorrectly can cause serious problems that may prevent your computer from booting properly. Microsoft cannot guarantee that any problems resulting from the configuring of BIOS/CMOS settings can be solved. Modifications of the settings are at your own risk.
1. Restart your computer.
2. Newer computers usually display a startup (or boot) menu. On the startup menu, select "BIOS setup," or "BIOS settings," or something similar.
Procedures vary depending on the BIOS manufacturer. Usually, you must press a key (such as F2, F12, Delete, Esc) or a key combination immediately after you turn on your computer but before Windows starts. For more information, check the information that came with your computer or go to the computer manufacturer's website.
3. The BIOS setup screen appears. On the BIOS setup screen, select the option called "Boot order," or something similar.
4. Select your main hard drive as the first startup device, save the setting changes, and then exit the BIOS.
5. Restart your computer.
BIOS: frequently asked questions
Hope this information is helpful. Please feel free to reply in case you face any other issues with Windows in future.