Saving Zip files on. OS Ventura Version 13.6.7 (22G720)

How are you sending these files to other people? I have had issues when sharing .zip files with some services such as Microsoft's SharePoint.

Have you ever tried to open the sent .zip files by either downloading them from the server or sending them to yourself if sent by e-mail?

What happens when they try to open those .zip files? What error message do they get and what app are they using to open them?

Other options include providing files to them in a folder in a cloud service (Dropbox, Google, Microsoft ... there are government versions of such cloud repositories) and setting up the folder so they can be accessed and downloaded.

https://www.7-zip.org/download.html offers a Mac version.

I might also add, TIFF and Raw photos are uncompressed. If you want to ensure the most compatible compressed file gets sent, use the Preview application in your Applications folder to open the photo file, and export as JPEG. The default compression amount is enough for most. Preview also offers functionality like resize.

Crop, resize, or rotate an image in Preview on Mac - Apple Support

Always keep the original uncompressed info on your computer and a backup hard drive or flash drive.

NHS has their own protections against personal identifiable information getting lost or stolen, and probably doesn't have the authority to install custom software such as Suffit Expander or 7-Zip on their Windows machines.

I would not even try to send photos to them. Your buddies there may have their own personal phones you can share photos on Facebook on, or Instagram.

https://www.playbook.com/

also offers free hosting of photo websties.

http://www.stuffit.com/ offers a decompression tool that can be used on Windows or Mac for those who have control over software installed on their systems.

If your Compress files being sent to them are unreadable, you may need to read about how to attach a MIME attachment with Mail:

Add attachments to emails in Mail on Mac - Apple Support

SCripps77 wrote:

Thanks for your help the NHS one was official they are expecting a response from me for a meeting files were scans of text saved as jpgs and had a similar thing with sending letters to a solicitor .I have just been sending myself some test files and they are not opening even when I have sent them using the right click drop down menu share option .The message I get is this file is not supported when sending to self . Yet if I am just opening them no problem at all

Exactly what I experienced using Microsoft's SharePoint a few years ago. I tried using .zip and .tgz archives and was unable to open either type even on the same computer where I had created & opened them prior to uploading & download from SharePoint. Unfortunately I did not have the time to do any other troubleshooting. I somewhat assumed the problem may have been due to the extremely large size of the archives, but was unable to get the time to test smaller archive files.

Maybe try changing the file extension on the file from ".zip" to ".zi1" or even ".jpg" to see if that makes any difference. I never tried that option. Firewalls & email scanners may be doing something to your file....in fact you may want to contact your IT department for assistance since it could be related to the email service and/or firewall or other security software & settings used on your Mac or your employer's systems. You would either need to right-click or Control-click on the file to get the context menu so you can select the proper macOS utility to open the file (Archiver?). Then try renaming the file extension back to ".zip" to see if the archive can be opened.

The Compress option available through the control key-mouse click in the Finder typically is probably the easiest way to make zip files on the Mac. If you have a mouse with a right mouse button it does the same function

Keep in mind compressing files can leave corrupted files in the end. It is better to get more storage to keep files uncompressed, than try to compress archives for indefinite storage.

The NHS needs to work out its own firewall issues for sending material back and forth. Likely certificates aren't working, etc. They need a common website where people can upload material. You are welcome to share with them the link to this thread which is static, to ask any questions about how to make their site more open for communication to the public.

Almost all image files are already compressed and can become larger when you compress them.

Unless you are sending hundreds of text files, I doubt you are gaining much.