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Download Abbreviated Help: How to Send & Receive Files with DropBox


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What is Cornell DropBox?
Cornell DropBox is a secure method for transferring files. Files are encrypted during transport over SSL (https://) using strong encryption only.
How long has Cornell had this service?
Since Spring 2006.
Who can use DropBox?
Any person with an active Cornell NetID or any individual with a valid email address who has been whitelisted by a Cornell community member.
Who should use DropBox?
Anybody who wants to transfer files securely to another person or computer. Do not send confidential information as an email attachment. Email is not secure!
Where can I use DropBox?
Anywhere there is a computer with an Internet connection and a supported web browser.
How long do files remain on DropBox?
The default automatic expiration is 14 days and can only be changed during upload. Optional expirations of 3, 7, and 21 dayes are available.
Can I extend the expiration of a file?
No. The expiration date of a file is set on upload. Neither sender nor receiver can extend the expiration once it has been uploaded. You may optionally download/upload the file again before the expiration date.
When am I logged out? Is there an inactivity timeout?
You are logged out after 30 minutes of inactivity. If you are in the middle of a file upload, you will not be forced to login until after your upload completes.
What does "Remember to use NetID Login option on this computer." do?
By selecting the checkbox and logging in, a cookie will be stored on the computer setting "NetID Login" as the default method. No private information is stored in the cookie, simply a Yes/No. You will still need to enter your NetID & Password everytime you login to DropBox. This option should not be used on public computers.

If a successful login is not completed after being automatically sent to CUWebLogin, the remember CUWebLogin will be automatically unchecked. Additionally you can logout and uncheck the box.
What is the 'Recent Activity' link on the bottom of the page?
As an extra layer of security when you are logged in, you can know exactly when and where your login has been used last on DropBox.
Can I change the name displayed when I send or download files?
No. The name displayed is pulled and updated automatically from the Cornell Directory.


IE6 users cannot access Cornell DropBox.
Effective October 26 2014, Cornell DropBox no longer supports SSLv3 for security concerns. Some users of IE6 may be unable to access the service. Users should use a more modern browser, include Google Chrome, Safari, Mozilla FireFox, or IE9+.
I cannot download a file, I receive a message "File Deleted".
Files sent via DropBox automatically expire after a number of days set by the sender. As soon as a file is expired or deleted, it is securely removed from the Cornell DropBox and cannot be retrieved. Additionally the sender can choose to delete the file at any time.

If you have missed downloading a file sent to you, you will need to contact the sender.
External Users: My Login PIN does not work or has expired.
Each time you login as an external user, you will login with a new Login PIN. When entering a Login PIN, the Login ID displayed in your browser must match the Login ID in the email from which you are copying the PIN. For more detailed instructions, see External Users - How to - Login.
External Users: I did not receive the Login PIN
In order to login to DropBox as an external user, you must be able to receive an email from in a timely fashion. Be sure to include this email address in your address book if your email client uses spam handling.

While rare, outages of Cornell email delivery do occur. You can view any services notices at Current status of IT services.
External Users: I made a mistake entering the Login PIN.
You will be presented another chance to enter the correct Login PIN. We suggest you copy and paste the Login PIN.
External Users: I'm asked for a password when sending/downloading files?
When a Cornell user adds you to their whitelist, they set a password for you that they need to share with you. Please contact the user who added you. If they do not recall, they can change the password.
External Users: During login, I receive "Not active on Cornell Whitelist."
The email address entered must match Cornell user's whitelist exactly. Your email added must match (case-insensitive). is not the same as

In addition, a whitelist expires after a default of 3 months. If you have used Cornell DropBox some time ago, you may need to have the Cornell sender renew you on their whitelist.
Upload of close to maximum/5GB failed.
If you are uploading several files totalling very close to the file limit and experiencing difficulty, please split up your upload for better success.
While sending/uploading files, my upload abruptly stopped or hung.
Please be sure to use a stable internet connection. If you are on a wireless or cellular connection, please verify your signal strength and network connectivity.
When using Internet Explore 9+, I cannot download files.
Internet Explorer 9+ features an optional setting "Do not save encrypted pages to disk". When selected by user or Active Directory group policy, this prevents many secure websites from working. Please use an alternate browser or change your browser policies.
When using Internet Explorer 11, I cannot change whitelist, blacklist or other settings.
Security options in Internet Explorer block certain asynchronous web functions, resulting in a black screen with a loading icon. Use an alternate browser or change your browser policies.
I do not see an upload sent to me.
Be sure the file was sent to you. If another user forwards an email, you will not be able to download the file through DropBox.
I no longer see the 'Grant' option.
Once a file has been deleted from DropBox, you may no longer grant a user access.
When sending a file, I receive "Search Failed - Not a NetID or Not Unique Enough Name."
If entering a search for a Cornell user, a search matching a single result could not be found. Please alter your search to be more specific or specify recipient in format.

If entering an external user's email address, please confirm the email address entered matches what appears on your whitelist (case-insensitive) and that the user has not yet expired from your whitelist. If you have made a typographical error when adding a user to your whitelist, you will need to remove the external user and add them again. For more detailed instructions on adding, removing, or renewing users on your whitelist, see Cornell Users - How to - Manage Whitelist.
During login, I receive "Blacklisted Email Address"
Certain email addresses are blocked from using the external user functionality. Please refer to the additional information displayed for further detail.
During login, I automatically get a Cornell Web Login screen.
If a previous user on the computer has chosen "Remember to use NetID Login option on this computer", click the back button in the browser to return to the standard login landing page which removes the default setting.

External Users and the Whitelist

What is the whitelist?
The whitelist allows users with a Cornell NetID to control if external users can send you files. By default external users cannot login and cannot send you files. If you whitelist an external user, you may then send them files and they you.
How many email addresses I can add to my whitelist?
There is no limit (within reason).
Is my whitelist private?
Yes and no. Malicious users cannot find out who is on your whitelist. However if they know an external user's email address, they can find out if they are on a whitelist -- but they won't know who whitelisted them.
Why set a whitelist password?
Setting a password for an external user on your whitelist adds an extra step in preventing a malicious user from accessing files you send to the external user. With a whitelist password, if a malicious user gained access to an external user's email account they would also need to know the whitelist password in order to download files. You should never send the whitelist password through email. The whitelist password should not be used as any other password.

When the external user goes to view the file recipients, notes, history or download the file, they will be prompted for the password. This password will apply to all files you send the external user.
What are the whitelist password requirements?
In order to ensure strong security on passwords for external users, the following are the minimum requirements for a password.

- be at least 7 characters long
- include at least 3 of following: lower case, upper case, numbers, special characters/symbols
- not be the email address, sender NetID, or other common dictionary word
Can we whitelist for all Cornell users?
No. DropBox access is managed by individual users. At this time DropBox does not allow specific external users be enabled to send files unrestricted to Cornell recipients.
Can I add to my whitelist?
No. With the exception of and, email addresses in the domain cannot be added. These users should use a Cornell NetID.
Can external users change their password?
External users cannot change the password set by the user. The password is unique to each individual and external user pair and is used only for purposes of transferring files within that pair. The Login ID/PIN (one-time password process) ties external users to their own account.
I do business with many Cornell users. Can I be given access to everyone?
No. DropBox access is managed by individual users. At this time DropBox does not allow specific external users be enabled to send files unrestricted to Cornell recipients.
To whom can external users send files?
External users can only send files to Cornell community members who have added them to their whitelist.
Why can't an external user close the browser during login?
In order to ensure a secure login, the browser session is uniquely tied to the Login PIN sent.
Why doesn't DropBox just send a link to login?
This model has been chosen to prevent "replay" and man-in-the-middle attacks on email.
What is the whitelist expiration?
You may choose 1, 3, or 6 months as the expiration time for an external user on your whitelist. At any point you may return to the whitelist and remove the user from your whitelist.
When I add an external user do they automatically receive an email?
No. A typical user may choose to add several external users and then communicate uniformly. DropBox will always notify you when an email is about to be sent and give you the option not to send it. For example when you send a file, you have the option (default is YES) to notify the recipient via email.

Sending/Uploading Files

What is the maximum file size?
You may send up to 5GB of files at once, BUT this upload must be completed within 1 hour. If you are accessing DropBox via wireless or non-Cornell network connection, your upload limit will be significantly lower.

Please note that when uploading large files, you must wait until you receive the File Uploaded message. If you surf away from the page, your upload will stop.
Can I upload a directory?
You will need to compress/zip the directory first.
Can I send files to myself?
Cornell community members can send files to themselves by entering their own NetID on Prepare Upload. External users cannot send files to themselves.
Can I send files on behalf of another user?
Can I send files to an Exchange Group Account?
Can I send files to a Cornell email alias/
This is not supported. Please use the format. You may wish to use the People Finder if you have difficulty finding the correct individual.
Can I send files to a Cornell mailing list?
No. Files cannot be sent to addresses matching Additionally email addresses cannot be added as an external user.
Can I forward the email so another person can download the file?
No. Files sent via DropBox are for specified recipients only. Forwarding the email notification of a file does not enable the recipient to download the file. In order for a user to download the file via DropBox they must have been granted access by the sender.

The original sender may optionally Revoke or Grant File Access.
Can I grant or revoke multiple files at a time?
Where did the <space> or special characters in the filename go?
DropBox sanitizes filenames to remove many special characters and spaces.
Why do I receive "Directory Hidden" when sending/receiving a file?
In order to protect a user's privacy, DropBox uses only public Cornell Directory information to identify a user.

In some cases when sending or receiving a file you will see a Directory Hidden message -- you should consider this a check to confirm you are sending a correct NetID. A problematic example would be a user who intends to send a file to someone they regularly deal with, but they mistype the NetID and wind up hitting a directory suppressed person. Please exercise great caution when sending files.
Why do I receive "receiver list includes external users" when sending files?
When sending files to external users, DropBox presents a informational message to remind users they are sending files outside the domain.