https://www.icyphoenix.com/viewtopic.php?f=4&t=1514&p=11360#p11360
-----------------------------------
Zuker
Thu 05 Apr, 2007 15:45

DEBUG - Blank Pages After Upgrading
-----------------------------------
If you are experiencing problems after Icy Phoenix installation, the problem could be related to one or a combination of the following:

[list][*]Corrupted files
[*]Wrong CHMOD
[*]Overwritten includes/DEF_ files with empty ones
[*]Corrupted THEMES table
[*]Corrupted Cache[/list]

[b]First of all make a full site backup, and then you can try one or more of the following:[/b]

[list][*]Reuploading all files (pay attention to not replace anything you may need and always make a backup first)
[*]Replacing includes/DEF_ files with fresh ones
[*]Applying correct CHMOD permissions
[*]Synchronizing FORUMS
[*]Uninstalling all styles and install them from scratch (empty themes table and manually add Ice style)
[*]Empty the CACHE folder (delete all files but [b].htaccess[/b] and [b]index.html[/b])
[*]Optimizing and Repairing DB (usually via phpMyAdmin)[/list]

Try to have a look at this as well: http://www.icyphoenix.com/viewtopic.php?t=1520

There is only one problem... if is the DEF_AUTH being corrupted... then the only solution is to reset the AUTH table. This can happen when upgrading from some old phpBB version with corrupted AUTH table or with some incorrectly deleted users.


