If you have contacts in Outlook and would like to synchronize with Salesforce, you need to consider the following
1- Contacts without a Company/Account (orphan contacts)
Easily mark these contacts for sync using the “Mark for sync” button (Marking a contact for sync, adds the salesforce.com value to that contact’s categories field) and next time you can hit the sync button and they will be synchronize to Salesforce
2- Contacts with a Company/Account
If you have contacts in Outlook with Account (company) names you will still be able to mark them for sync, associate them with the Account and use the sync button to synchronize them to salesforce.
Even if you have the newest Outlook edition that has the "auto mark for sync" option under Tools | Salesforce.com Options | Contacts tab, you still won’t be able to mark any contacts with the company name for sync without associating them manually
In order to sync these type of contacts, you need to manually associate each contact to its account in Salesforce
if the account already exist in Salesforce and if the account doesn't exist in Salesforce you need to use the "quick create" button to create the account in Salesforce and then associate it
This method obviously won’t work if you have 100+ contacts with Account (Company) names, so the best and easiest way is to:
1- Export your contacts from Outlook into a .CSV file
2- Then using the Salesforce import wizard upload them into Salesforce.
To access the import wizard you need to be a Salesforce system Administrator and you can access this tool from Setup | Administration setup | Data Management | Import Accounts/Contacts
3- Once you are done with the import, move your contacts from the Outlook Contacts folder into a different folder (you may need to create a new folder in Outlook) in Outlook and make sure the main Contacts folder is empty so it will bring down all the contacts from Salesforce without creating any duplicate
** if you don't (re)move your contacts from the Contacts folder you will get duplicates in Outlook. One with salesforce.com category and another with a different category or none
4- From Outlook go to Tools | Salesforce Options
5- On the General tab, check the box for "Delete history and start synchronize from scratch" and click on ok
6- Go to Outlook and click on sync and you should be able to synchronize all your contacts from Salesforce back to Outlook with the proper Account association
To export contacts from Outlook into a csv file
Select File | Import and Export... from the menu.
Make sure Export to a file is highlighted.
Click Next >.
Now make sure Comma Separated Values (Windows) is selected.
Click Next > again.
Highlight the Contacts folder.
Click Next >.
Use the Browse... button to specify a location and file name for the exported contacts. Something like "Outlook.csv" or "ol-contacts.csv" on your Desktop should work fine.
Click Next > (once more).
Now click Finish.