Fix Your Missing Guitar Hero World Tour DLC Songs After Playing GH5 Wii

Have your Guitar Hero World Tour DLC songs disappeared after playing Guitar Hero 5? Every time you play GH5, it breaks your GHWT SD Card DLC, so next time you load GHWT, you'll get the error message pictured above, which reads:
ERROR: Add-on Content on the SD Card cannot be listed due to a missing or out of date content catalog. To restore SD Card functionality, please redownload content in the music Store or restore content in the Archive.
It sounds bad, but it's really a 30 second fix.
Just open up the Music Store from the Guitar Hero World Tour main menu, and click the orange Archive button:

As soon as you click the Archive button, it will offer to fix your DLC:

This process only takes 3 seconds. Afterwards, your SD card DLC songs will appear as normal:

A Possible Solution to Avoid This in the First Place
I was able to avoid this problem by using two separate SD cards (since GHWT can't handle SDHC cards, larger than 2GB). I use one 2GB card for GHWT, and the key is to always remove it before loading GH5!
This ends up working out pretty well, since the size of all the Guitar Hero 5 song imports like Guitar Hero Smash Hits and Band Hero easily adds up to more than 2GB.
The strange thing is, sometimes this method works, sometimes it doesn't. I know for certain that this DID avoid the "Missing content catalog" error a few times, but then I inexplicably got the error again afterwards.
Do you know a better solution? Post it in the comments.
Thanks, this could be useful when I play with my friend who owns GHWT (he didn't get GH5, yet). Keep up the good work.
"….since GHWT can't handle SDHC cards, larger than 2GB…." I wonder if that's what is making my SDHC unreadable–loading content from GH5, then playing GHWT.
I'm almost certain that GHWT will not work with any SDHC cards, regardless of whether they've been used with GH5 or not.
Rock Band 2 for Nintendo Wii suffers from this same 2GB SD card limitation. (No SDHC support)
I could have been a little more clear I guess:
1) Save DLC to an SDHC with GH5
2) Then switch to GHWT leaving the SDHC in
3) Then switching back to GH5 leaves GH5 complaining that my SDHC is unreadable.
Even the Wii Data management says the card is unreadable at that point. I've tried this with a 16Gb and 8Gb card.
Just looking for others to confirm this behavior on their system.
Hmm I've got a SanDisk brand blue-and-red 8GB SD Card about 3-4 GB full, and I can do what you propose in steps 1-2-3 and never have I even one time, experienced the "Unreadable" error that you're getting.
However I have heard of this before on forums so I know you're not the only one. Not sure what to suggest though!