Editing the Category.aspx page filter in a blog site breaks the category filter.
You change the default view of a category that filters the blog posts on a Microsoft Windows SharePoint Services 3.0 blog site. When you visit the SharePoint Services 3.0 blog site, and then you click the link for the category that you changed, the blog posts are not filtered correctly. Instead, all the blog posts are displayed.
SOLUTION:
a) Create a new blog site that uses the same language and categories as the broken one. We'll call this new blog site the "temp" site.
b) Use SharePoint Designer (SPD) to open both the broken and the temp site. You will have each site open in its own instance of SPD.
c) On both instances of SPD, expand the folder tree to Lists | Categories, and open Category.aspx in split mode.
d) On both instances of SPD, select the "Posts" Web part in the design view part of the spilt.
e) For the broken Category.aspx page, locate the <ListViewXML tag on the code section for the Posts Web part. Copy only the GUID from the "View Name= <GUID>" section.
f) Paste this GUID over the same place on the temp Category.aspx page. Here, you are swapping GUIDs, "broken" to "temp."
g) On the temp Category.aspx page, copy the entire code between the <ListViewXML... and </ListViewXML> tags.
h) Paste this chunk of code over top of the same <ListViewXML section of broken Category.aspx page. Here, you are swapping the entire ListViewXML section, "temp" to " broken."
i) Save the changes to the broken page.
j) Examine your broken blog site. It should be fixed now.
k) You can now delete the temp blog site. As a summary of these steps, you are copying the entire ListViewXML section for the Posts Web part on the temp site and overwriting the same section on the broken site. However, you have to keep the View Name GUID from the broken site so that you copy that to the temp site first.
This has now been officially recognized a bug by MS.
