I was going to post this in the Software section but it's Win 7 related because I don't get the error on my other PC using Win XP Ver 2002 SP3.
I was trying to edit my web page, just adding a photo and then just tried changing a word and it won't save it.

I'm using Microsoft Frontpage 2003 ver 11.5516.5606 and there are currently no updates.

I get message:

Server Error: The server extensions were unable to access the file “…\_vti_pvt\service.lck”.

Please check the file permissions.

Contact your Internet service provider or Web server administrator for more information.