SVN does not show Log

[Сергей 33]

Hello
We use svnserver 1.7.8 for FreeBSD
 
We use  TortoiseSVN 1.6x and 1.7x o n Client computers
 
The  TortoiseSVN on  Client computers can not show LOG.
 
I was doing a TortoiseSVN->Show Log which results in a "Want to go offline?" 
window with message
"There has been a problem contacting the server. Do you want to see the cached 
data instead?"
 
And then show empty list with data 1970-01-01
 
 
Help please.