You can look at what file types can be attached to documents in EBYS from https://faq.cc.metu.edu.tr/faq/what-kind-files-can-be-attached-documents-ebys.

In internal documents;

• 15 MB is the maximum size for a single file.
• In total, 100 MB can be attached to one document.

In external documents;

• 15 MB is the maximum size for a single file.
• If the department you want to send the document to has a KEP that is PTTKEP, 100 MB in total can be attached to one document.
• If the department you want to send the document to has a KEP that is not PTTKEP, 25 MB in total can be attached to one document.
• If there is at least one KEP address that is not PTTKEP in the distribution list, this situation will limit the maximum file size limit to 25 MB.

Questions about EBYS can be directed to ebys-destek@metu.edu.tr