Repository > + > Upload file: Update all upload error messaging
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# Context
https://gitlab.com/gitlab-org/gitlab/-/issues/525474#note_2429651766
# Problem
When users try to upload a file in `Repository` \> `+` \> `Upload file`, and there is an error, the error message appears as an alert that is difficult to see behind the modal.
In https://gitlab.com/gitlab-org/gitlab/-/issues/525474 and https://gitlab.com/gitlab-org/gitlab/-/merge_requests/185237, the error for dragging a directory into the modal was updated:

However, there are still other error messages for uploading files that still appear as alerts behind the modal. See error message for uploading a file with the same name as an existing file in the directory:

# Design recommendation
* [ ] Provide list of all the error messages in `Repository` \> `+` \> `Upload file` for UX/technical writing review
* [ ] Update the formatting of all error messages in the upload file modal to use this formatting, so users can see the error messages clearly:

* [ ] Update the text of the error message for uploading a file of the same name to: `This file name already exists. Please choose a different name and try again.`
* [ ] If necessary, make other error message text more descriptive and specific rather than the generic ~~`Error uploading file. Please try again.`~~
issue