It is sometimes difficult or rather impossible to delete or edit a web part. When clicked on “Modify Shared web part” link, error page appeared
“An unexpected error has occurred.”
One way to delete the web part is to go to web part maintenance page and delete it. This can be done by adding “?contents=1” to default.aspx page.
An example can be http://portal/sitedirectory/abc/default.aspx?contents=1