You can use ctrl-pageup/ctrl-pagedown to go between visible worksheets.
If that works for you, maybe you just can't see the worksheet tabs.
Tools|options|View tab|check sheet tabs.
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Maybe the tabs are just too far to the left. Use those VCR like arrow keys in
the bottom left to scroll those tabs to the right.
Maybe your tabs are just off the worksheet window.
Window|arrange|Tiled (and resize manually).
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Other options could be that there is only one worksheet in that workbook--or
that the worksheets are hidden (or even very hidden).
Format|sheet
can you choose Unhide.
If yes, unhide them (one by one).
if no, one more spot to check.
Open your workbook
hit alt-f11 to get to the VBE
hit ctrl-r to see the project window.
Find your workbook's project
It should look kind of like: VBAProject (yourfilenamehere.xls)
Click on that once.
Hit the asterisk on the numeric keypad to expand all its branches.
You should see
Microsoft Excel Objects
Under that tree, you'll see the sheet names (with their codenames)
and an object named "ThisWorkbook"
The sheetnames look like:
Sheet1 (NameYouCanSeeOnTheWorkSheetTabInExcel)
Do you have multiple sheets there?
Hit F4 to see the properties window
Then you can click on each (one at a time)
scroll down in the properties window looking for Visible.
What do you see?
If it's not Visible, change it to visible.
If you save your workbook with all the sheets visible and then reopen it and
some are hidden, then maybe there's a macro running that hides them when you
open the workbook. See the developer for help if that's the case.
