When you migrate WIKI site from WSS or MOSS to SharePoint 2010; you might face following error as shown in below screen shot in “Recently Modified” section that “An error has occurred on the server.”
This problem is primarily because of indexing settings in the SharePoint.
The error occurs if you have not configured any column for indexing in MOSS. To solve the issue, you can either add a column for indexing in MOSS before Migration or add a column for indexing in SharePoint 2010 after Migration.
Please refer to the following for the details:
To add a column for indexing, please follow the steps shown below.
Open the settings of the Pages Library. Scroll down to Indexed columns as shown in the image below.
Click Indexed column and you will redirected to a new page as shown below.
Click on Create a new index in the page shown above and you will redirected to a page as shown below. Select Modified column and click Create.
You will see the column has been added that you selected.
Go back to Site and you will see that the error is gone.
Hope this helps!