OK, I've had enough of this.
My mom's family's business is having problems with their two computers, which we'll call PC1 and PC2. Both are running Windows 7, and they used to have some shared folders. But for maybe the past couple of weeks, they're not sure how long, that hasn't been working. PC2 was able to see PC1 (it showed up under "Network"), but not access any files in there. (Folders, yes; either it could see those or it remembered them.) PC1 couldn't see PC2 at all.
After fiddling with a whole bunch of junk and rebooting PC2, I managed to make it show up on PC1. But when I click on "PC2," it says "Windows cannot access \PC2." Pinging PC2's IP address (at least the one that showed up under "IPv4 Address" when I ran
ipconfig on PC2) turned up nothing -- request timed out.
The name of the network is the same in Network and Sharing Center on both computers, as are the type and the workgroup name under System (the latter being the thing I changed on PC2 before rebooting). It's a little inconsistent on whether "PC1" is capitalized as such or as "pc1." The router's a 2Wire 1701HG Gateway. Aside from that, I don't know what to look for -- if it's a firewall issue or what. LANs aren't exactly my field of expertise.
EDIT: Forgot to mention -- both computers have Internet access.