Paring down Google mail for migration to Office 365 mail
These instructions offer advice on reducing their your Google mail before migrating to Office 365 mail. The transfer process requires a significant amount of syncing and copying and reducing your Google mail before you begin will speed up the migration.
These instructions are to be done prior to following the instructions for migration found here. However, you may want to read through the migration instructions in order to get acquainted with the process as these instructions reference them.
Understanding Folders and Labels before deleting messages
The first thing to consider is that Google mail uses labels and not folders. With a mail system that uses folders, such of Office 365 mail, if you move a message from the Inbox to a folder it is no longer in the Inbox and it resides only in the folder you moved the message to. Two folders cannot contain the same message. You can copy an message and paste it into another folder but then you have 2 messages residing in two different folders.
However, Google mail uses labels, which are more like pointers that reference the same message. One email can be included in many labels but there is still only one message. Therefore, deleting a message that exists in one label but also exists in another will delete it from both. If you delete an email that belongs both to your Inbox label (yes, the inbox is a label too) and another label which you have assigned for safe keeping, it be gone from both places.
These tips will discuss:
- keeping email which you have assigned to a label while paring down your inbox prior to a specific date
- finding and deleting advertising and email from mailing lists or newsletters
- permanently deleting email you do not wish to migrate
Preserve mail with Google labels that is also in the Inbox
If you wish to keep older mail that you have assigned to a label, prior to continuing with these instructions, be sure that mail is not also assigned to the Inbox label.
Click on a label
Here’s what to do
Details and pic below…
Because Thunderbird syncs even the deleted items from Google we need to do a process that deletes email completely from Google. A process that will render the messages unretrievable. Therefore, pick a date that before which you are certain that you will never need any those emails again.
In the Google search field type -has:userlabels before:(your date here)
Don’t forget the dash. This serves as a minus sign. We are telling Google to make a list that does NOT include labels you have created before a certain date.
Select the checkbox at the left that is above the first email in the list. This will select all the email that is currently being listed.
make sure that the list is sorted by “most recent” (top right)
Click “select all messages that match this search”.
Click the Trash button (This takes the email out of the Inbox).
Emptying the Trash
Since Thunderbird syncs deleted items we now have to empty the trash of all it’s messages. (remember, this is not retrievable)
Here’s how..
Click the Trash item in the left hand column (might be under “more”)
Select the “select all” checkbox once again
Click “select all X messages in Trash”
Click “Delete Forever” ( and they do mean forever)