Here's a collection of things to check, for various problems when printing a USPS label using the PayPal Shipping Center.

Except for when PayPal's server is down, almost all of these types of problems, regardless of the error message, is usually due to either a missing name or a bad address format.  Always look over your ship to address first for anything obviously not quite right, especially a missing name.  Another possible cause is a problem with your postage funding source.

Looking at the "address doesn't match" pop up window on the Shipping Label Screen, or using  USPS.com Find a Zip Code, check for even the slightest difference in the address.  Remove periods, comma's, etc., use St, Rd, Blvd, etc. You can not use St for "Saint" something in some addresses for example.  Look for things that should be on the 2nd address line and not the 1st. Watch for any spelling errors.  To maintain a confirmed address do not change the Zip Code.  Note that sometimes the Zip Codes shows as the error, but it really is the City that is wrong.

The "not available, not charged" message appearing after you click Print Shipping Label from the Transaction Details page, is usually a missing name.  Be aware that sometimes this is not evident unless you open the address with the Edit Function on the Shipping Label Screen so you can see the individual data fields.  There must be a name in both the First and Last name fields.  The exception for this is a business account name, which is not obvious from this screen, so try putting part of the name in the Last Name field.  This can also happen if the 1st and 2nd address fields are not used properly.

If you still think the address looks correct, but can not print a label, use the Edit Address Function to manually delete, and manually type each line back in (do not use cut and paste).  This will clear any bad or blank characters not visible.

Another occasional glitch to the "Not Available" problem is now even when you fix the address, you’re stuck with this message repeatedly.  The work around is to remember the correction needed to be made to the address.  Go back to your Account Overview page and from there click Print a Shipping label again.  Then go directly to Edit Address and put in the correction first, then continue on as usual.

If a transaction number was issued and you where charged, always try to reprint a label before voiding it.  There are three ways to reprint.  From the Payment Transaction Details, from the USPS Transaction Details, and from the link in the PayPal Email confirming You Created a Shipping Label.  If you get an error message, you may need to try all three if one doesn't work.  If you still can't reprint a label, retry after you print a new label from different transaction.

And yes, it seems one bad address in the middle of your Multi Order Shipping session fouls up the whole thing.  So it is always good to at least give the addresses a quick look over.   If a problem arises, you should still be able to go back and manually fix and reprint them one by one.

If all else fails, try printing your label manually using the following link, which circumvents the format checks.
https://www.paypal.com/shipnow  If you still get an error message, there may be a problem if your funding source for your postage payment is not your PayPal account balance.

Other problems can sometimes be corrected by clearing your cache (temporary internet files) and restarting your browser.  Also make sure your browser, Java Runtime, and Abode Reader are kept up to date and enabled.  Plus always insure your Pop Up Blocker and/or Firewall is enabled for PayPal.

If you are unable to print anything but the SAMPLE label, there is a known problem with some of the newer HP printers and Internet Explorer.  You can try this fix  in Internet Explorer, go to File > HP Smart Web Printing and uncheck it.   Another workaround is to use Firefox instead of IE.

For Firefox  and XP users, if your computer hangs asking permission to use the printer try this work around. When the check box appears and hangs your computer, open your Task Manager (ctrl-alt-del, and click Task Manager).  Now you will be able to check and continue without problem until you restart from either the hibernate or suspend mode. The problem is caused by the Java Runtime. Update to Java version 6 release 10 or later.