Step1: Press "Win + r" to open RUN window
Step2: Now enter "msconfig.exe" or just "msconfig" and hit enter.
Step3: In the first tab, i.e General tab, select the second option , ie, "Diagnostic Startup" to load basic devices and services. Now reboot your computer and it will boot in safe mode.
NOTE: After the above configuration, your computer will be set to restart in safe mode permanently. To get back to standard startup, follow upto the Step2, and in step 3, select the option 1 in general tab i.e "Normal Startup" to load all device drivers and startup items.