Incompatibility

• Incompatibility is a common cause of a BSOD. Newly installed software may not be compatible with the operating system, causing it to crash. Conflicting or redundant software, like having two or more anti-virus programs, may cause a BSOD. This is because the various anti-virus programs access the same files in the operating system. With all of them running simultaneously and performing the same tasks, they end up crashing the computer. Software and hardware incompatibility also causes a BSOD. For example, computers usually have recommended options for video software. Video software installed to a computer that is different from the recommended options may conflict with the video hardware on the computer, as computer manufacturers may not test the function of all available software.
  
  

Software Updates and Upgrades

• At times, update or upgraded software can cause a system to crash. When a BSOD happens right after an update or upgrade, the most likely culprit for the crash is the updated software. This happens because computer manufactures may not full test updates and upgrades in different computer environments. Upgrading the entire operating system may also cause a BSOD because newer operating systems may not be compatible with some of the older software installed on the computer. Reverting the software to earlier versions can resolve the BSOD.
  
  

Insufficient Memory

• A computer has RAM, or random access memory, that it uses to run programs. All programs running on a computer occupy an address space in the memory. Different programs require different memory space allocation, with complex programs requiring more memory than the others do. When too many applications run simultaneously, this can tax the computer's memory. A BSOD can occur when the computer finally runs out of memory.
  
  

Malware

• Viruses or other malicious software can inflict damage to a computer. Some viruses make the computer unusable or inaccessible by causing the computer to restart every time. These viruses attack the system files that operate the computer. Some viruses delete valid system files and replace them with infected files. Others corrupt the system files making them inoperable. When this happens to important system files, the computer may crash.