After upgrading a TPLink wireless router to an Asus RT N66U router, all our various machines see each other and show file data in Home Group except for the Acer 4220 laptop.
I can see the 4220 in the Home Group BUT I can not access file date from the main machine. From the 4220, I can access file data on my main machine, so it works ok in that direction. But, not other machines.
When using the Home Group problems shooter, it says that the 4220's system clock and local time are not synchronised. When I ask it to fix the problem, it says it can not make that fix.
After trying many solutions I found in a Google search which do not work, I tried a manual time sync using the time on my main machine - after many attempts it is not possible to press a key quick enough sync to the millisecond :)
I tried to sync the 4220 to the Atomic Clock in Colorado using AtomClock utility - when applying it says it is not able to adjust the system clock.
Some solutions suggest it is an out of date BIOS. The 4220 is 2.5 yrs old.
File exchange was fine before I installed the Asus router - which has excellent user feedback.
After the Asus router install, I had to run netsh winsock reset and IPV6 and 4 interface reset to get any homegroup machines to appear on any machine.
All other machines can file exchange, just the 4220 can not from it to another machine
Any suggestions, pleeeeease.