[Xperia Z2 Android Development] fezzawinkle:
No it doesn't matter what kind of attachment. Here is a snapshot of what is going on.

02-28 00:50:47.232 4403 11886 D NetworkSecurityConfig: Using Network Security Config from resource network_security_config debugBuild: false

02-28 00:50:47.232 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.236 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.237 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.240 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.240 4403 11886 W DownloadManager: [34391] Stop requested with status HTTP_DATA_ERROR: Unable to resolve host "android.clients.google.com": No address associated with hostname

02-28 00:50:47.243 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.243 5350 5513 E Gmail : DownloadListener: no rows found in cursor

02-28 00:50:47.244 4403 11886 D DownloadManager: [34391] Finished with status WAITING_TO_RETRY

02-28 00:50:47.270 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.270 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.274 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.274 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.278 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.279 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.282 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.283 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.283 5350 5513 E Gmail : DownloadListener: no rows found in cursor

02-28 00:50:47.299 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.300 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.303 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.304 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.308 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.308 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.311 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.312 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.314 5350 5901 I Gmail : AttachmentManager.cancelAttachmentDownload attachmentId=14, oldFileUriOrName=3.12 Kw with Power Optimisers.pdf, SD=0, redownload=false, error=-1

02-28 00:50:47.326 5350 5513 E Gmail : DownloadListener: no rows found in cursor

02-28 00:50:47.339 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.340 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.343 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.344 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.348 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.348 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.351 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.351 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.353 4403 4403 W DownloadManager: Odd, no details found for download 34219

02-28 00:50:47.370 5350 5513 E Gmail : DownloadListener: no rows found in cursor

02-28 00:50:47.375 5350 5901 I Gmail : AttachmentManager: start downloading attachment 14 dlid=34392, conversationId: 1560455973286665327, messageId: 1560455973286665327, partId: 0.1, rendition: SIMPLE, saveToSd: false

02-28 00:50:47.383 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.383 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.390 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.391 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.391 4403 11888 D DownloadManager: [34392] Starting

02-28 00:50:47.396 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.396 5350 11389 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.399 5350 11389 E Gmail : Couldn't find local attachment

02-28 00:50:47.400 5350 11389 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.404 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.404 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.414 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.415 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.419 4403 11888 D NetworkSecurityConfig: Using Network Security Config from resource network_security_config debugBuild: false

02-28 00:50:47.420 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.421 4403 11888 W DownloadManager: [34392] Stop requested with status HTTP_DATA_ERROR: Unable to resolve host "android.clients.google.com": No address associated with hostname

02-28 00:50:47.421 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.421 4403 11888 D DownloadManager: [34392] Finished with status WAITING_TO_RETRY

02-28 00:50:47.423 5350 5513 E Gmail : DownloadListener: no rows found in cursor

02-28 00:50:47.429 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.430 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.435 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.436 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.441 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.442 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.447 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.449 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.453 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.454 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.460 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.460 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.464 5350 5513 E Gmail : DownloadListener: no rows found in cursor

02-28 00:50:47.464 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.465 5350 11387 I Gmail : Unable to decode thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/SIMPLE/false: class java.io.FileNotFoundException Missing local attachment.

02-28 00:50:47.469 5350 11387 E Gmail : Couldn't find local attachment

02-28 00:50:47.470 5350 11387 I Gmail : Unable to get orientation of thumbnail content://gmail-ls/stuart.simington@gmail.com/messages/32/attachments/0.1/BEST/false: class java.io.FileNotFoundException Missing local attachment.