It does not matter how much free space you have on the hard drive. What matters is how much space you have on the / partition.
If I encountered this problem, I would reinstall Mint 17 to the same partition, WITHOUT FORMATTING the partition. That would preserve the settings you have.
Mint 17 Cinnamon (64 bit), Quad core AMD A8-3870 with Radeon HD Graphics 6550D, 8GB DDR3, Ralink RT2561/RT61 802.11g PCI
Microsoft-free environment since 1996
To help Linux Mint with a donation, please visit http://www.linuxmint.com/donors.php