Network credentials only retained for a period.

Hi,

I have a Server 2008 and Windows 7 VM setup and in both instances I'm having problems with the network credentials to other servers being retained.

I have one credential linked to a web server address where I'm asked to enter the password on a daily basis. If I enter the password and check the box to retain the credential appears to persist until some point during the early hours of the next morning and then the cycle repeats. 

I know it's a bit of a broad query but any suggestions on what to look for? 

Thanks