Im able to merge the unallocated space with C with Minitool Partition Wizard Free Ver too. The different is that i do merge the unallocated space with Win10 EFI System Partition, then resize it back to 300mb (it wont allow me to resize it to 100mb). after that resize C partition adding the balance of unallocated space. Now my local C drive is 14.7gb free of total 27.6gb. 🙂
