Resolved gh-444 by adding the new phpspreadsheet library, and removing the old PHPExcel library.

admin/compiler/joomla_3/script.php

@@ -96,6 +96,14 @@ class com_###component###InstallerScript
 		if ($type === 'install')
 		{###PREINSTALLSCRIPT###
 		}
+		// check if the PHPExcel stuff is still around
+		if (JFile::exists(JPATH_ADMINISTRATOR . '/components/com_###component###/helpers/PHPExcel.php'))
+		{
+			// We need to remove this old PHPExcel folder
+			$this->removeFolder(JPATH_ADMINISTRATOR . '/components/com_###component###/helpers/PHPExcel');
+			// We need to remove this old PHPExcel file
+			JFile::delete(JPATH_ADMINISTRATOR . '/components/com_###component###/helpers/PHPExcel.php');
+		}
 		return true;
 	}
 
@@ -120,5 +128,106 @@ class com_###component###InstallerScript
 		{###POSTUPDATESCRIPT###
 		}
 		return true;
+	}
+
+	/**
+	 * Remove folders with files
+	 * 
+	 * @param   string   $dir     The path to folder to remove
+	 * @param   boolean  $ignore  The folders and files to ignore and not remove
+	 *
+	 * @return  boolean   True in all is removed
+	 * 
+	 */
+	protected function removeFolder($dir, $ignore = false)
+	{
+		if (JFolder::exists($dir))
+		{
+			$it = new RecursiveDirectoryIterator($dir);
+			$it = new RecursiveIteratorIterator($it, RecursiveIteratorIterator::CHILD_FIRST);
+			// remove ending /
+			$dir = rtrim($dir, '/');
+			// now loop the files & folders
+			foreach ($it as $file)
+			{
+				if ('.' === $file->getBasename() || '..' ===  $file->getBasename()) continue;
+				// set file dir
+				$file_dir = $file->getPathname();
+				// check if this is a dir or a file
+				if ($file->isDir())
+				{
+					$keeper = false;
+					if ($this->checkArray($ignore))
+					{
+						foreach ($ignore as $keep)
+						{
+							if (strpos($file_dir, $dir.'/'.$keep) !== false)
+							{
+								$keeper = true;
+							}
+						}
+					}
+					if ($keeper)
+					{
+						continue;
+					}
+					JFolder::delete($file_dir);
+				}
+				else
+				{
+					$keeper = false;
+					if ($this->checkArray($ignore))
+					{
+						foreach ($ignore as $keep)
+						{
+							if (strpos($file_dir, $dir.'/'.$keep) !== false)
+							{
+								$keeper = true;
+							}
+						}
+					}
+					if ($keeper)
+					{
+						continue;
+					}
+					JFile::delete($file_dir);
+				}
+			}
+			// delete the root folder if not ignore found
+			if (!$this->checkArray($ignore))
+			{
+				return JFolder::delete($dir);
+			}
+			return true;
+		}
+		return false;
+	}
+
+	/**
+	 * Check if have an array with a length
+	 *
+	 * @input	array   The array to check
+	 *
+	 * @returns bool/int  number of items in array on success
+	 */
+	protected function checkArray($array, $removeEmptyString = false)
+	{
+		if (isset($array) && is_array($array) && ($nr = count((array)$array)) > 0)
+		{
+			// also make sure the empty strings are removed
+			if ($removeEmptyString)
+			{
+				foreach ($array as $key => $string)
+				{
+					if (empty($string))
+					{
+						unset($array[$key]);
+					}
+				}
+				return $this->checkArray($array, false);
+			}
+			return $nr;
+		}
+		return false;
 	}###MOVEFOLDERSMETHOD###
 }