diff --git a/src/protocols/rdp/rdp_fs.c b/src/protocols/rdp/rdp_fs.c
index ab48cc2f..d32da681 100644
--- a/src/protocols/rdp/rdp_fs.c
+++ b/src/protocols/rdp/rdp_fs.c
@@ -402,7 +402,7 @@ int guac_rdp_fs_open(guac_rdp_fs* fs, const char* path,
 
 }
 
-int guac_rdp_fs_read(guac_rdp_fs* fs, int file_id, int offset,
+int guac_rdp_fs_read(guac_rdp_fs* fs, int file_id, uint64_t offset,
         void* buffer, int length) {
 
     int bytes_read;
diff --git a/src/protocols/rdp/rdp_fs.h b/src/protocols/rdp/rdp_fs.h
index 9168efb1..8148725e 100644
--- a/src/protocols/rdp/rdp_fs.h
+++ b/src/protocols/rdp/rdp_fs.h
@@ -487,7 +487,7 @@ int guac_rdp_fs_open(guac_rdp_fs* fs, const char* path,
  *     error occurs. All error codes are negative values and correspond to
  *     GUAC_RDP_FS constants, such as GUAC_RDP_FS_ENOENT.
  */
-int guac_rdp_fs_read(guac_rdp_fs* fs, int file_id, int offset,
+int guac_rdp_fs_read(guac_rdp_fs* fs, int file_id, uint64_t offset,
         void* buffer, int length);
 
 /**