Since index drive out of space in EV email archive server and purchase new disk under processing.
We have some ev users already resigned and their index under index drive (eg: D:\EV Indexing\Index1\index5\xx1_4375)
May i know how can remove those folder to release space?
You need the index to be able to search the archive. Officially, it is not advised to remove the index, specifically for this reason. However, if you need to free space fast, you can EMPTY the index folder for the archive. I strongly advise NOT to remove the actual folder. If there is a need to search that archive, you will need to rebuild the index for that archive. To 'officially' remove it, you will need to remove the archive. That however might not be possible due to retention policies. If you use DA in your company, I would indeed move the indexes of those resigned users to another location.