unable to rename 'core\core.a'; reason: File exists

Hi All,

I am getting this error while compiling the code. I've started getting this error all of sudden, earlier it's working fine. I am using NodeMCU. Even I am getting this error in all Arduino IDE sample examples also.
Error Code
C:\Users\sm00342631\AppData\Local\Arduino15\packages\esp8266\tools\xtensa-lx106-elf-gcc\2.5.0-3-20ed2b9/bin/xtensa-lx106-elf-ar: unable to rename 'core\core.a'; reason: File exists

exit status 1
Error compiling for board Generic ESP8266 Module.

Your help/suggestion are much appreciated.

Thanks in advance

Look at the slashes!