No sign in function for the front office after update

[asgllccb]

I started this topic in the 1.6 forums and essentially didn't get a response.  Hopefully someone might be able to help here.  

After updating successfully from 1.4.4.1 to 1.6.x ( I have tested updating to almost all 1.6 versions beginning with the newest as recommended by prestashop, all with the same result)  I have been searching and trying everything I can for days (now weeks) to resolve the problem of not having the "sign in" function in the front page of my test update site.  Please know that I am working on a backed up version of my site on a wamp server that I upgraded.  Anyway, I have noticed by comparing a test fresh install with my update that the block "displaynav" in my positions or in my database is no where to be found.  This is the block that the sign in function is located in for the fresh install.  Is this block necessary for the "sign in" feature to exist and work in 1.6, if so, how can I get it? If not, please let me know so this can be ruled out to other possiblites that may be causing this loss.  

[asgllccb]

Update.  Again, not sure if this is going to make a difference but, again, comparing a fresh install to my update it appears that the sign in functioning occurs through the user info block (aside perhaps from what hook it is assigned to).  I can see the user info block there using the live edit feature, but it seems it may not be working right because, even though it is there, the sign in feature is not.  The association is there in the back office in module positions, where, among other places, the user info block is associated with the header display and top display blocks.  Anyone have any ideas?  I am doing the best I can trying to go through a file by file, line by line comparison between my fresh install of 1.6.0.8 and update, to see if I can see any difference in coding that might get this to work but nothing so far.  I would think the prestashop people or other programmers with more experience with prestashop might be able to guide me in what to look for, but I haven't heard anything from anyone.  The sign in feature is a pretty big need for a functioning shopping cart...please someone help.

[vekia]

have you got an access to database manager like phpmyadmin ?

[asgllccb]

Yes, thank you.  After a lot of testing and comparison, my test site picked up that there was an update for the user info module (the update was not showing up before).  I updated it, still didn't work, so I reset it (the module) and the browser cache, set prestashop to force recompile and it worked!  Suuuch a relief.  Thank you prestashop for the update fix on the module for 1.6X!  Thank you Vekia for responding.