What have you done to remove this low disk space problem?
In my experiences, the ways for you to resolve this low disk space problem could be different according to your different conditions:
* If there is too unnecessary files or programs stored on this C partition, clean them all up to free some free space.
* If there is enough free space on other partition, like D, E or F partitions, you can open Disk Management, delete or shrink the partition with free space and add the free space to your C partition there.
* If the free space is not adjacent to your C partition, you also can use a partition resizing tool to extend this partition, like GParted, IM-Magic Partition Resizer Free and Active Partition Master, etc.
* But, if there is no any free space left on the same physical drive, just buy a larger one to replace the old one.
No matter what your conditions are, just save all partition data on other places in case of data loss.
Read more information here:
partition-magic-server-2003.blogspot.com/2013/11/resize-server-2003-partition-free.html