Cannot return to GoogleGroups: Update Email Address

[FrontierDigest]

System goes to "Update Email Address" page after signing in (see attached snapshot).
Unlike one previously posted in Google Groups Guide, the issue shows "Removed Addresses:" with nothing specified.

Under "Change Existing Subscriptions", the drop-down box shows current (Yahoo) email address and others are names used with Picasa web posting (with domain "@gmail.com" appended).

However, clicking [Change Address] or [Leave Address] loops back to same page.  Someone having this problem is successful with [Change Address] (to same old current "gmail" address) and the Groups page is resumed.  Noticeable differences are current address and web browser which are GMail and Firefox2 (above is Yahoo and IE7).

[Gigabyte2]

After several tries, the account appears to be unlinked from Google.
When it is signed up again, it can escape from this page but however
has permenently lost former subscription (or even ownership!) of old
groups! :-(

[Gigabyte2]

A solution found

Given current situation that:
1) The defective account has email changed from original. But, via
some linking mechanism inside Google, it retains membership/ownership
of old groups (despite of new email address)
2) The old email address becomes unknown to Google. Signing up again
makes it new account to Google and has no membership/ownership to any
group.

Although the defective account cannot pass "Update Email Address"
page, note the first link under "Edit your Google-account addresses"
section. Following the link, it goes to the list of groups. Then,
for group that we have manager/owner privilege, there is a link next
to its name going to members management. We can add the original
email address back from there (either direct adding name, or use new
account of old address to request group joining and then use the
defective account to grant permission).