I have created the custom object Project and I would like to change the standard layout and replacing by a visualforce page displaying data with
different subtabs for each project record. To do this I used an existing template posted in a forum that works for a STANDARD obect account and that displays subtabs for each account records, using a view overriding standard layout and using a visualforce layout (https://www.salesforce.com/us/developer/docs/pages/Content/pages_quick_start_tabs.htm)

the begining of code for the visualforce page "tabbedAccount" is as follow :
<apex:page standardController="Account" showHeader="true"   
    tabStyle="account" >
<style>
.activeTab {background-color: #236FBD; color:white; background-image:none}
.inactiveTab { background-color: lightgrey; color:black; background-image:none}
</style>
.......
</apex:page>

I created a new visualforce page named "TabbedProject" and replaced "Account" by "Project__c" as follow :

<apex:page standardController="Project__c" showHeader="true"   
    tabStyle="Project__c" >
.......
</apex:page>

When saving the page i have an error message displaying the following error :
Unknown property 'Project__cStandardController.account'

Moreover when editing the view in the Project object and trying to override existing layout, i cannot select any visualforce page (emplty list)


I would be very grateful if someone could help me on this topic !
Thank You !