While setting up the Amazon S3 Setup connection, you can see a red button but no description of the error.
For CRM For Outlook versions 1.0.57 to 1.0.61 a bug was present that would in some circumstances result in a red bar upon testing even with working credentials. This has been fixed for any later version and a hotfix for version 1.0.61 is available attached to this article. Just copy and replace "Attachments.dll" and "Boyum.Utilities.dll" in the server installation folder ("C:\Program Files (x86)\Boyum IT\CRM for Outlook Server") with the files found in "Attachments_Hotfix_1.0.61_Server.zip". This should ensure that Amazon S3 does not fail in creating a valid bucket in some situations.
If this did not solve your problem please check the following:
The red color means it cannot perform the necessary connection to Amazon S3. It's just a test, but it's almost certain this means it's not going to work for real as well although you should test it if everything seems correct. It's hard to give a more exact error since we don't get a good error message back from Amazon, but here is the list of probable options:
1) Wrong Access Key or Secret Key. Could be a simple copy/paste problem. Did it add a space at the end, did it cut of a character? This should be double checked.
2) Was the user created with the correct permissions. Specifically was it given "AmazonS3FullAccess" permission: