File Sharing on a Network Using Windows 7

Good morning everybody !

This is my issue!!! With 4 Pcs on a network,users usually access the sharing folder on the Admin's Pc,but when someone just add a new file, i cannot see that new file from my computer by accessing the sharing folder,i always have to research that Pc under / run / and type the IP @ of that PC to re enter into the sharing folder while some PCs easily access that new file .

How to fix it ?

Thanks in advance!