Product navigation looping, Shop menu in admin not working and usergroup issue

[sagaranvekar]

Hello,

Website is on -
Joomla 4.2.7
Virtuemart 4.0.12 10777
PHP 8.0.27

• Product navigation :
  Show product navigation is turned on. But there is weird issue. Product navigation is not there on first product in a particular category. When clicked on 2nd, it keeps on looping between 3 products only.
  No matter if I switch to Cassiopeia template or horme_3 template provided by Virtuemart. Vmbeez3 template makes everything blank.
  
  


• Shop error
  When I go to Virtuemart -> Shop in admin, it is showing error:
  

  0 count(): Argument #1 ($value) must be of type Countable|array, null given

  When I switch to PHP 7.3.33, the error goes away!
  
  


• Configuration error
  When I go to Virtuemart -> Configuration, it is showing this error:
  

  Serious security issue detected: Your #__usergroups table includes incorrect datas and permissions reported at backend might not be same as permissions applied on frontend. Please fix your #__usergroups. Just edit a joomla user group and store it. This should update the table.

  
  

Any help on these issue will be greatly appreciated.

[jenkinhill]

1. The navigation issue is known, a fix should be in a later release.  Vmbeez3 is a Joomla 3 template, it does not work in J4.

2. Do you have a third-party plugin which needs upgrading for PHP8?  An error trace would help identify.

3. See the required action given in that message!  See http://forum.virtuemart.net/index.php?topic=148272.msg528805#msg528805

[sagaranvekar]

Thank you very much for your reply @jenkinhill.

• I will wait for VM release with product navigation fix. Probably this issue pops up after every major release.
• I was able to resolve it. There was that Joomla issue "Unable to load user with ID: 62" on some Joomla admin pages. That made me think that this issue is related. So, probably shop vendor was user id 62 and as vendor was missing, it might caused that issue. So, I changed vendor user id using 'Set store owner' option in 'Tools & Migration'.
• The solution you provided for issue no 3 worked! Thank you very much.