diff --git a/application/utils.inc.php b/application/utils.inc.php
index 47a532503..6b69cbf16 100644
--- a/application/utils.inc.php
+++ b/application/utils.inc.php
@@ -563,48 +563,86 @@ class utils
 
 	public static function ReadFromFile($sFileName)
 	{
-		if (!file_exists($sFileName)) return false;
+		if (!file_exists($sFileName)) {
+			return false;
+		}
+
 		return file_get_contents($sFileName);
 	}
 
 	/**
 	 * Helper function to convert a value expressed in a 'user friendly format'
 	 * as in php.ini, e.g. 256k, 2M, 1G etc. Into a number of bytes
+	 *
 	 * @param mixed $value The value as read from php.ini
+	 *
 	 * @return number
 	 */
-	public static function ConvertToBytes( $value )
+	public static function ConvertToBytes($value)
 	{
 		$iReturn = $value;
-	    if ( !is_numeric( $value ) )
-		{
-	        $iLength = strlen( $value );
-	        $iReturn = substr( $value, 0, $iLength - 1 );
-	        $sUnit = strtoupper( substr( $value, $iLength - 1 ) );
-	        switch ( $sUnit )
-			{
-	            case 'G':
-	                $iReturn *= 1024;
-	            case 'M':
-	                $iReturn *= 1024;
-	            case 'K':
-	                $iReturn *= 1024;
-	        }
-	    }
-        return $iReturn;
-    }
-  
-  /**
-   * Checks if the memory limit is at least what is required
-   *
-   * @param int $memoryLimit set limit in bytes
-   * @param int $requiredLimit required limit in bytes
-   * @return bool
-   */
-  public static function IsMemoryLimitOk($memoryLimit, $requiredLimit)
-  {
-      return ($memoryLimit >= $requiredLimit) || ($memoryLimit == -1);
-  }
+		if (!is_numeric($value)) {
+			$iLength = strlen($value);
+			$iReturn = substr($value, 0, $iLength - 1);
+			$sUnit = strtoupper(substr($value, $iLength - 1));
+			switch ($sUnit) {
+				case 'G':
+					$iReturn *= 1024;
+				case 'M':
+					$iReturn *= 1024;
+				case 'K':
+					$iReturn *= 1024;
+			}
+		}
+
+		return $iReturn;
+	}
+
+	/**
+	 * Checks if the memory limit is at least what is required
+	 *
+	 * @param int $iMemoryLimit set limit in bytes
+	 * @param int $iRequiredLimit required limit in bytes
+	 *
+	 * @return bool
+	 */
+	public static function IsMemoryLimitOk($iMemoryLimit, $iRequiredLimit)
+	{
+		return ($iMemoryLimit >= $iRequiredLimit) || ($iMemoryLimit === -1);
+	}
+
+	/**
+	 * Set memory_limit to required value
+	 *
+	 * @param string $sRequiredLimit required limit, for example '512M'
+	 *
+	 * @return bool|null null if nothing was done, true if modifying memory_limit was successful, false otherwise
+	 *
+	 * @uses utils::ConvertToBytes()
+	 * @uses \ini_get('memory_limit')
+	 * @uses \ini_set()
+	 * @uses utils::ConvertToBytes()
+	 *
+	 * @since 2.7.5 N°3806
+	 */
+	public static function SetMinMemoryLimit($sRequiredLimit)
+	{
+		$iRequiredLimit = static::ConvertToBytes($sRequiredLimit);
+		$sMemoryLimit = trim(ini_get('memory_limit'));
+		if (empty($sMemoryLimit)) {
+			// On some PHP installations, memory_limit does not exist as a PHP setting!
+			// (encountered on a 5.2.0 under Windows)
+			// In that case, ini_set will not work
+			return false;
+		}
+		$iMemoryLimit = static::ConvertToBytes($sMemoryLimit);
+
+		if (static::IsMemoryLimitOk($iMemoryLimit, $iRequiredLimit)) {
+			return null;
+		}
+
+		return ini_set('memory_limit', $iRequiredLimit);
+	}
 
 	/**
 	 * Format a value into a more friendly format (KB, MB, GB, TB) instead a juste a Bytes amount.
diff --git a/pages/ajax.render.php b/pages/ajax.render.php
index 688b670d1..fcba420a1 100644
--- a/pages/ajax.render.php
+++ b/pages/ajax.render.php
@@ -2060,7 +2060,9 @@ EOF
 
 		case 'xlsx_run':
 			$sMemoryLimit = MetaModel::GetConfig()->Get('xlsx_exporter_memory_limit');
-			ini_set('memory_limit', $sMemoryLimit);
+			if (utils::SetMinMemoryLimit($sMemoryLimit) === false) {
+				IssueLog::Warning("XSLX export : cannot set memory_limit to {$sMemoryLimit}");
+			}
 			ini_set('max_execution_time', max(300, ini_get('max_execution_time'))); // At least 5 minutes
 
 			$sToken = utils::ReadParam('token', '', false, 'raw_data');
@@ -2068,8 +2070,7 @@ EOF
 			$oExcelExporter = new ExcelExporter($sToken);
 			$aStatus = $oExcelExporter->Run();
 			$aResults = array('status' => $aStatus['code'], 'percentage' => $aStatus['percentage'], 'message' => $aStatus['message']);
-			if ($aStatus['code'] == 'done')
-			{
+			if ($aStatus['code'] == 'done') {
 				$aResults['statistics'] = $oExcelExporter->GetStatistics('html');
 			}
 			$oPage->add(json_encode($aResults));
diff --git a/pages/csvimport.php b/pages/csvimport.php
index 0b6024479..9f4b566a2 100644
--- a/pages/csvimport.php
+++ b/pages/csvimport.php
@@ -17,21 +17,24 @@
  * You should have received a copy of the GNU Affero General Public License
  */
 
-try
-{
-	ini_set('memory_limit', '256M');
+try {
 	require_once('../approot.inc.php');
 	require_once(APPROOT.'/application/application.inc.php');
 	require_once(APPROOT.'/application/itopwebpage.class.inc.php');
 	require_once(APPROOT.'/application/ajaxwebpage.class.inc.php');
-	
+
 	require_once(APPROOT.'/application/startup.inc.php');
-	
+
 	require_once(APPROOT.'/application/loginwebpage.class.inc.php');
+
+	if (utils::SetMinMemoryLimit('256M') === false) {
+		IssueLog::Warning('csvimport : cannot set minimum memory_limit !');
+	}
+
 	LoginWebPage::DoLogin(); // Check user rights and prompt if needed
 	
 	$iStep = utils::ReadParam('step', 1);
-	
+
 	$oPage = new iTopWebPage(Dict::S('UI:Title:BulkImport'));
 	$oPage->SetBreadCrumbEntry('ui-tool-bulkimport', Dict::S('Menu:CSVImportMenu'), Dict::S('UI:Title:BulkImport+'), '', utils::GetAbsoluteUrlAppRoot().'images/wrench.png');
 
@@ -1542,4 +1545,3 @@ catch(Exception $e)
 		IssueLog::Error($e->getMessage());
 	}
 }
-?>
diff --git a/test/application/UtilsTest.php b/test/application/UtilsTest.php
index 47c9d4d97..d3a308e7b 100644
--- a/test/application/UtilsTest.php
+++ b/test/application/UtilsTest.php
@@ -426,4 +426,26 @@ class UtilsTest extends \Combodo\iTop\Test\UnitTest\ItopTestCase
 			],
 		];
 	}
+
+	/**
+	 * @param string $sExpressionToConvert
+	 * @param int $iExpectedConvertedValue
+	 *
+	 * @dataProvider ConvertToBytesProvider
+	 */
+	public function testConvertToBytes($sExpressionToConvert, $iExpectedConvertedValue)
+	{
+		$iCurrentConvertedValue = utils::ConvertToBytes($sExpressionToConvert);
+		self::assertEquals($iExpectedConvertedValue, $iCurrentConvertedValue, 'Converted value wasn\'t the one expected !');
+	}
+
+	public function ConvertToBytesProvider()
+	{
+		return [
+			'123' => ['123', 123],
+			'56k' => ['56k', 56 * 1024],
+			'512M' => ['512M', 512 * 1024 * 1024],
+			'2G' => ['2G', 2 * 1024 * 1024 * 1024],
+		];
+	}
 }