diff --git a/wire/core/Fields.php b/wire/core/Fields.php
index 5281507f..6846047d 100644
--- a/wire/core/Fields.php
+++ b/wire/core/Fields.php
@@ -658,6 +658,7 @@ class Fields extends WireSaveableItems {
 			$field2->flags = 0; // intentional overwrite after above line
 		}
 		$field2->name = $field2->name . "_PWTMP";
+		$field2->prevFieldtype = $field1->type;
 		$field2->type->createField($field2); 
 		$field1->type = $field1->prevFieldtype;
 
diff --git a/wire/modules/Fieldtype/FieldtypeFile/FieldtypeFile.module b/wire/modules/Fieldtype/FieldtypeFile/FieldtypeFile.module
index 34d8598d..d37f6464 100644
--- a/wire/modules/Fieldtype/FieldtypeFile/FieldtypeFile.module
+++ b/wire/modules/Fieldtype/FieldtypeFile/FieldtypeFile.module
@@ -1073,7 +1073,7 @@ class FieldtypeFile extends FieldtypeMulti implements ConfigurableModule, Fieldt
 		$schema['keys']['created'] = 'index (created)';
 		$schema['keys']['filesize'] = 'index (filesize)'; // 3.0.154+
 		
-		if($field->id) {
+		if($field->id && !$field->prevFieldtype) {
 			if($field->flags & Field::flagFieldgroupContext) {
 				$field = $this->wire('fields')->get($field->name);
 			}