My All mighty Tenant admin, Primary Site Admin, Other Site Admin, Only site admin, Site collection admin, you name it admin cannot upload a wsp to solution gallery at one of my sharepoint site. When I try to upload a file I can select my wsp but then I get "You dont have permission to 'this' site"
I can upload this to other sites
In the wsp there is a workflow, exported from SPD
Should not make a difference whether it has SPD workflow or not. The question is can you save a site as a template (assuming non-publishing). If you cannot, then there is a possibility the site collection is corrupted and you would have to raise a support ticket with Microsoft or discard if not too late.
I did the Powershell method and it worked for me...
http://www.evokeit.com/sharepoint-online-deny-permission-when-uploading-custom-masterpage/
