Casio tough solar databank Model DB-E30-1AV, resets to 12:00AM, 1 January 2000, in the middle of the night. After returning it to the proper time, after about 5 minutes the watch resets again to 12:00AM, 1 January 2000 Type of watch:

It's possible that some part in your watch hasn't been put back (properly) during the replacement procedure of the battery. I'd advise you to go back to the service point and let them check if all the internal part are complete (and in their right position)

Hi ,you can download watch manuals from here.
You can probably adjust it manually.

Today my 6-year old Waveceptor has adjusted itself to daylight Savings time without my intervention. I was agreeably surprised. For all the years I have had the watch, I kept the module manual by my side just for the two times a year I have to adjust the time.
All this to tell you that you imperatively have to read the module's manual. If you do not have it visit the Casio Worldwide web site and download it. You need the module number. You will find it on the back of the watch. It is a 4-digit number inside a rectangle.

remove battery and wait about two minuteslook http://www.pmwf.com/Watches/Casio/FirstMemoryProtectReset.htmand for other casio watches

You can get instructions from the Casio web site.

Go to the casio web site "casio.com".

Select "support" and the "manuals",
watches;

Accept terms

Select "watch manual archive"

Read the number of the back of your watch and enter it into the search box

Write down the four-digit module number from the watch back, and go to this link for full info in PDF format:

http://world.casio.com/wat/download/en/manual/

Good luck, Bill

If you haven't got instructions on how to do this, you can get
instructions from the Casio web site.

Go to the casio web site "casio.com".

Select "support" and the "manuals",
watches;

Accept terms

Select "watch manual archive"

Read the number of the back of your watch and enter it into the search box

It may be that the watch is working in one of the "settings"modes.

If you do not have any instructions you can get them from their web site.

Go to the casio web site "casio.com".

Select "support" and the "manuals", watches;

Accept terms

Select "watch manual archive"

Read the number of the back of your watch and enter it into the search box

how do I reset a Casio lap memory 50 or 60 watch

If your databank is like mine (DB-35H), there is a TINY spring in a really unusual spot that you probably didn't notice that fell out. Laying the watch face down and with the back off, there is a little tiny hole in the back towards one of the corners. (sorry, already put my watch back together and didn't notice which corner.) There is a tiny (1/16" x 1/4") spring that sits upright in that hole. It must make a contact with the metal cover. I replaced my battery and when I did, a spring fell out. I looked all over the internet, then wrote Casio, who said they didn't have access to the information about where the spring went. (Doh!) I got a used DB-35H from my brother and was going to swap the innards when I noticed the spring on his. Put my spring back and it beeps! If you've lost the spring, don't know if you can fake it with tinfoil or not, but it really is a TINY spring. Good luck.