DHCP leases and subnets on Server 2003R2

[farmeunit]

To make a long story short, I had to re-subnet our network so I could re-organize it and fix a few things. I also deleted the VLANs temporarily so they're using the same DHCP server and we put in all new switching.

The problem is that I'm getting quite a few conflicting IPs and Bad Addresses on the DHCP Server (Windows 2003R2). Is there a way to get this to work itself out quicker? Leases are set to 2 days right now. Could I set them to say 6 hours or 12 hours temporarily? Would that make a difference? We have about 350 devices connecting, so it's not a huge amount.

Any advice would be great. Thanks!

Additional Info: I just set "Enable Conflict Detection" to 1. It was 0. Hopefully that'll help?

[+BudMan MVC]

so you deleted all your vlans - so you went to just a flat network? Ie single large address space to allow for all your 350 devices? something like 192.168.0.0/23

Does this new dhcp scope overlap with your old address space? If so then sure you could have issues if detection wasn't working - and clients were running on their old leases.

if changing to new address space, I would of made sure you new address space did not overlap with your old address space.

Where there any devices with static IPs that overlap with your new address space.