Export throws the folloeing error: Mimetype not currently mapped: 'application/octet-stream'


I’ve just upgraded our Octopus from 3.4.14 to 3.11.1.
I got the same error on the old version as well as on the new one while trying the export wizard:
2017-02-24 14:44:08.3983 1 FATAL Mimetype not currently mapped: 'application/octet-stream’
at Octopus.Core.Util.MimeType.ToExtension(String mimeType) in MimeTypes.cs:line 53
at Octopus.Core.Model.Projects.Project.get_AttachmentReferences in Project.cs:line 87
at Octopus.Migrator.ExportProcess.ExportWriter.ExportAttachments(IId obj) in ExportWriter.cs:line 119
at Octopus.Migrator.ExportProcess.ExportController.WriteProject(IEnumerable1 projects) in ExportController.cs:line 155 at Octopus.Migrator.ExportProcess.ExportController.Export() in ExportController.cs:line 81 at Octopus.Shared.Startup.AbstractCommand.Octopus.Shared.Startup.ICommand.Start(String[] commandLineArguments, ICommandRuntime commandRuntime, OptionSet commonOptions, String displayName, String version, String informationalVersion, String[] environmentInformation, String instanceName) in AbstractCommand.cs:line 78 at Octopus.Shared.Startup.OctopusProgram.Start(ICommandRuntime commandRuntime) in OctopusProgram.cs:line 234 at Octopus.Shared.Startup.ConsoleHost.Run(Action1 start, Action shutdown) in ConsoleHost.cs:line 77
at Octopus.Shared.Startup.OctopusProgram.Run() in OctopusProgram.cs:line 106

I’ve found the following 2 similar support discussions:
but it couldn’t help me in solving this issue


Hi Nir,

Thanks for getting in touch and reporting this issue! We have had a couple of similar reports recently, and have fixed them accordingly by increasing our supported logo types a little wider. Problem is, what file extension is an application/octet-stream supposed to be? :slight_smile:

After researching deeper I found that we really didn’t need MimeType/file-extension as part of the import/export process, so I’ve removed our brittle code dependence completely: https://github.com/OctopusDeploy/Issues/issues/2562

You watch that issue to see when it ships. In the meantime you could try re-uploading your project logo with one of the more common image types like PNG, JPG, GIF, etc.

Hope that helps!

Hi Michael,

Thanks for your response I wasn’t sure which project is the one causing this and why, but your answer gave me a lead, and I now understand what needs to be done to work around this issue:
Basically the Export wizard was failing every time it reached a project with this logo, so the last one that was created in the Projects export folder was the problematic one which I just changed it to the default, and repeated this for the next similar failures, until I got a successful export

Kind regards,

Nir Weinberg