# Incompatibility of Library and Preserve file modification time options **URL:** \ **Category:** Support\ **Created:** [March 5, 2023, 2:08pm UTC](https://community.mp3tag.de/t/incompatibility-of-library-and-preserve-file-modification-time-options/60275 "2023-03-05T14:08:17Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![olivierq02](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/o/8e7dd6/32.png) [@olivierq02](https://community.mp3tag.de/u/olivierq02)\ **Post date:** [March 5, 2023, 2:08pm UTC](https://community.mp3tag.de/t/incompatibility-of-library-and-preserve-file-modification-time-options/60275/1 "2023-03-05T14:08:17Z")
Hello everyone After reading several posts, I think the "library" and "Preserve file modification time when saving tags" options are incompatible. Indeed, it seems that the library is only reloaded if the file modification dates are changed. Can you confirm it to me? ---
**Author:** ![LyricsLover](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/l/c6cbf5/32.png) [@LyricsLover](https://community.mp3tag.de/u/LyricsLover)\ **Post date:** [March 5, 2023, 3:37pm UTC](https://community.mp3tag.de/t/incompatibility-of-library-and-preserve-file-modification-time-options/60275/2 "2023-03-05T15:37:32Z")
Are these answers a valid confirmation? > [@Library - force rebuild](https://community.mp3tag.de/t/library-force-rebuild/19755/2): > > You have to refresh thefile-view of the loaded files. MP3Tag does not refresh them "on the fly". That has nothing to do with the library. The library only gets updated during refresh or new load if the timestamp has changed. including the one from Florian: > [@Library - force rebuild](https://community.mp3tag.de/t/library-force-rebuild/19755/5): > > Just for completeness: you can also select all relevant files files and use "File \> Read Tag" or [Ctrl+T] to refresh the library data from the file system. ---
**Author:** ![ohrenkino](https://community.mp3tag.de/user_avatar/community.mp3tag.de/ohrenkino/32/4843_2.png) [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)\ **Post date:** [March 5, 2023, 4:43pm UTC](https://community.mp3tag.de/t/incompatibility-of-library-and-preserve-file-modification-time-options/60275/3 "2023-03-05T16:43:38Z")
> [@olivierq02](#): > > Indeed, it seems that the library is only reloaded if the file modification dates are changed. The library works all the time when switched on. If you use MP3tag to modify a file but set the option to preserve the modification date, MP3tag still knows that the file has changed and updates the library. So if the file has not been changed in the meantime, nothing is lost. Any changes outside MP3tag that also preserve the modification date will make MP3tag skip the update when reading the file next time. So, no: these 2 options are not incompatible as the are both managed by MP3tag. Anything outside MP3tag cannot be controlled by MP3tag. ---
**Author:** ![olivierq02](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/o/8e7dd6/32.png) [@olivierq02](https://community.mp3tag.de/u/olivierq02)\ **Post date:** [March 6, 2023, 12:22pm UTC](https://community.mp3tag.de/t/incompatibility-of-library-and-preserve-file-modification-time-options/60275/4 "2023-03-06T12:22:41Z")
Thank you for your answers which satisfy me. I had a library problem but I understood why afterwards: I had worked on 2 different workstations and therefore 2 MP3Tags. ---
**Author:** ![system](https://community.mp3tag.de/uploads/default/original/2X/c/ce7035d426cb755a7916793326d23b465222a407.png) [@system](https://community.mp3tag.de/u/system)\ **Post date:** [April 5, 2023, 12:23pm UTC](https://community.mp3tag.de/t/incompatibility-of-library-and-preserve-file-modification-time-options/60275/5 "2023-04-05T12:23:40Z")
This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.